Progress in the development of subunit vaccines for gastrointestinal nematodes of ruminants.

Science.gov (United States)

Matthews, J B; Geldhof, P; Tzelos, T; Claerebout, E

2016-12-01

The global increase in anthelmintic resistant nematodes of ruminants, together with consumer concerns about chemicals in food, necessitates the development of alternative methods of control for these pathogens. Subunit recombinant vaccines are ideally placed to fill this gap. Indeed, they are probably the only valid option for the long-term control of ruminant parasitic nematodes given the increasing ubiquity of multidrug resistance in a range of worm species across the world. The development of a subunit multicellular parasite vaccine to the point of practical application would be a groundbreaking step in the control of these important endemic infections of livestock. This review summarizes the current status of subunit vaccine development for a number of important gastrointestinal nematodes of cattle and sheep, with a focus on the limitations and problems encountered thus far, and suggestions as to how these hurdles might be overcome. © 2016 John Wiley & Sons Ltd.

Dengue vaccines: Challenges, development, current status and prospects

Directory of Open Access Journals (Sweden)

A Ghosh

2015-01-01

Full Text Available Infection with dengue virus (DENV is the most rapidly spreading mosquito-borne viral disease in the world. The clinical spectrum of dengue, caused by any of the four serotypes of DENV, ranges from mild self-limiting dengue fever to severe dengue, in the form dengue hemorrhagic fever (DHF and dengue shock syndrome (DSS. Increased rates of hospitalization due to severe dengue, during outbreaks, result in massive economic losses and strained health services. In the absence of specific antiviral therapy, control of transmission of DENV by vector management is the sole method available for decreasing dengue-associated morbidity. Since vector control strategies alone have not been able to satisfactorily achieve reduction in viral transmission, the implementation of a safe, efficacious and cost-effective dengue vaccine as a supplementary measure is a high public health priority. However, the unique and complex immunopathology of dengue has complicated vaccine development. Dengue vaccines have also been challenged by critical issues like lack of animal models for the disease and absence of suitable markers of protective immunity. Although no licensed dengue vaccine is yet available, several vaccine candidates are under phases of development, including live attenuated virus vaccines, live chimeric virus vaccines, inactivated virus vaccines, subunit vaccines, DNA vaccines and viral-vectored vaccines. Although some vaccine candidates have progressed from animal trials to phase II and III in humans, a number of issues regarding implementation of dengue vaccine in countries like India still need to be addressed. Despite the current limitations, collaborative effects of regulatory bodies like World Health Organization with vaccine manufacturers and policy makers, to facilitate vaccine development and standardize field trials can make a safe and efficacious dengue vaccine a reality in near future.

Development of respiratory syncytial virus (RSV) vaccines for infants.

Science.gov (United States)

Gerretsen, Hannah E; Sande, Charles J

2017-06-01

2017 will mark the 60 th anniversary since the first isolation of RSV in children. In spite of concerted efforts over all these years, the goal of developing an effective vaccine against paediatric RSV disease has remained elusive. One of the main hurdles standing in the way of an effective vaccine is the fact that the age incidence of severe disease peaks within the first 3 months of life, providing limited opportunity for intervention. In addition to this complexity, the spectre of failed historical vaccines, which increased the risk of illness and death upon subsequent natural infection, has substantially increased the safety criteria against which modern vaccines will be assessed. This review traces the history of RSV vaccine development for young infants and analyses the potential reasons for the failure of historic vaccines. It also discusses recent breakthroughs in vaccine antigen design and the progressive evolution of platforms for the delivery of these antigens to seronegative infants. © 2017 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Progress in Childhood Vaccination Data in Immunization Information Systems - United States, 2013-2016.

Science.gov (United States)

Murthy, Neil; Rodgers, Loren; Pabst, Laura; Fiebelkorn, Amy Parker; Ng, Terence

2017-11-03

In 2016, 55 jurisdictions in 49 states and six cities in the United States* used immunization information systems (IISs) to collect and manage immunization data and support vaccination providers and immunization programs. To monitor progress toward achieving IIS program goals, CDC surveys jurisdictions through an annual self-administered IIS Annual Report (IISAR). Data from the 2013-2016 IISARs were analyzed to assess progress made in four priority areas: 1) data completeness, 2) bidirectional exchange of data with electronic health record systems, 3) clinical decision support for immunizations, and 4) ability to generate childhood vaccination coverage estimates. IIS participation among children aged 4 months through 5 years increased from 90% in 2013 to 94% in 2016, and 33 jurisdictions reported ≥95% of children aged 4 months through 5 years participating in their IIS in 2016. Bidirectional messaging capacity in IISs increased from 25 jurisdictions in 2013 to 37 in 2016. In 2016, nearly all jurisdictions (52 of 55) could provide automated provider-level coverage reports, and 32 jurisdictions reported that their IISs could send vaccine forecasts to providers via Health Level 7 (HL7) messaging, up from 17 in 2013. Incremental progress was made in each area since 2013, but continued effort is needed to implement these critical functionalities among all IISs. Success in these priority areas, as defined by the IIS Functional Standards (1), bolsters clinicians' and public health practitioners' ability to attain high vaccination coverage in pediatric populations, and prepares IISs to develop more advanced functionalities to support state/local immunization services. Success in these priority areas also supports the achievement of federal immunization objectives, including the use of IISs as supplemental sampling frames for vaccination coverage surveys like the National Immunization Survey (NIS)-Child, reducing data collection costs, and supporting increased precision

Laser vaccine adjuvants. History, progress, and potential.

Science.gov (United States)

Kashiwagi, Satoshi; Brauns, Timothy; Gelfand, Jeffrey; Poznansky, Mark C

2014-01-01

Immunologic adjuvants are essential for current vaccines to maximize their efficacy. Unfortunately, few have been found to be sufficiently effective and safe for regulatory authorities to permit their use in vaccines for humans and none have been approved for use with intradermal vaccines. The development of new adjuvants with the potential to be both efficacious and safe constitutes a significant need in modern vaccine practice. The use of non-damaging laser light represents a markedly different approach to enhancing immune responses to a vaccine antigen, particularly with intradermal vaccination. This approach, which was initially explored in Russia and further developed in the US, appears to significantly improve responses to both prophylactic and therapeutic vaccines administered to the laser-exposed tissue, particularly the skin. Although different types of lasers have been used for this purpose and the precise molecular mechanism(s) of action remain unknown, several approaches appear to modulate dendritic cell trafficking and/or activation at the irradiation site via the release of specific signaling molecules from epithelial cells. The most recent study, performed by the authors of this review, utilized a continuous wave near-infrared laser that may open the path for the development of a safe, effective, low-cost, simple-to-use laser vaccine adjuvant that could be used in lieu of conventional adjuvants, particularly with intradermal vaccines. In this review, we summarize the initial Russian studies that have given rise to this approach and comment upon recent advances in the use of non-tissue damaging lasers as novel physical adjuvants for vaccines.

The recent progress in RSV vaccine technology.

Science.gov (United States)

Fretzayas, Andrew; Papadopoulou, Anna; Kotzia, Doxa; Moustaki, Maria

2012-12-01

The most effective way to control RSV infection would be the development of an expedient and safe vaccine. Subunit vaccines, live attenuated RSV vaccines, plasmid DNA vaccines have been tested either in human or in mouse models without reaching the ultimate goal of efficacy and safety, at least in humans. Viruses such as adenovirus, sendai virus, measles virus were also used as vectors for the generation of RSV vaccines with promising results in animal models. Recent patents describe new techniques for the generation of candidate vaccines. These patents include virus like particles as vaccine platforms, recombinant RSVs or modified RSV F protein as component of the vaccine. Despite the number of the candidate vaccines, the new RSV vaccines should overcome many obstacles before being established as effective vaccines for the control of RSV infections especially for the young infants who are more susceptible to the virus.

Development of a vaccine for bacterial kidney disease in salmon

International Nuclear Information System (INIS)

Kaatari, S.; Turaga, P.; Wiens, G.

1989-08-01

This document is the executive summary and background review for the final report of ''Development of a Vaccine for Bacterial Kidney Disease in Salmon''. A description of the disease is provided, with microbiological characterization of the infective agent. A brief discussion of attempts to eradicate the disease is included. Recent progress in vaccine development and attempts to control the disease through pharmacological means are described, along with potential ways to break the cycle of infection. 80 refs

Large animal models for vaccine development and testing.

Science.gov (United States)

Gerdts, Volker; Wilson, Heather L; Meurens, Francois; van Drunen Littel-van den Hurk, Sylvia; Wilson, Don; Walker, Stewart; Wheler, Colette; Townsend, Hugh; Potter, Andrew A

2015-01-01

The development of human vaccines continues to rely on the use of animals for research. Regulatory authorities require novel vaccine candidates to undergo preclinical assessment in animal models before being permitted to enter the clinical phase in human subjects. Substantial progress has been made in recent years in reducing and replacing the number of animals used for preclinical vaccine research through the use of bioinformatics and computational biology to design new vaccine candidates. However, the ultimate goal of a new vaccine is to instruct the immune system to elicit an effective immune response against the pathogen of interest, and no alternatives to live animal use currently exist for evaluation of this response. Studies identifying the mechanisms of immune protection; determining the optimal route and formulation of vaccines; establishing the duration and onset of immunity, as well as the safety and efficacy of new vaccines, must be performed in a living system. Importantly, no single animal model provides all the information required for advancing a new vaccine through the preclinical stage, and research over the last two decades has highlighted that large animals more accurately predict vaccine outcome in humans than do other models. Here we review the advantages and disadvantages of large animal models for human vaccine development and demonstrate that much of the success in bringing a new vaccine to market depends on choosing the most appropriate animal model for preclinical testing. © The Author 2015. Published by Oxford University Press on behalf of the Institute for Laboratory Animal Research. All rights reserved. For permissions, please email: journals.permissions@oup.com.

[Dengue, zika, chikungunya and the development of vaccines].

Science.gov (United States)

Kantor, Isabel N

2018-01-01

Dengue (DENV), zika (ZIKV) and chikungunya (CHIKV), three arbovirosis transmitted by Aedes mosquitoes, have spread in recent decades in humid tropical and subtropical zones. Dengue is epidemic in subtropical areas of Argentina. DENV infection confers lasting immunity against the infecting serotype but increases the risk of serious disease upon reinfection by any of the other three. The recombinant tetravalent vaccine Dengvaxia® prevents severe dengue and hospitalization in seropositive subjects. In 2017, Dengvaxia was approved in Argentina, for ages 9 to 45, but is not included in the national vaccination calendar. Two other vaccines are in Phase III evaluation: one developed by NIAID / Instituto Butantan and the other by Takeda. ZIKV, a virus associated with microcephaly in newborns in Brazil, circulates since 2016 in Argentina. There is still not effective treatment nor vaccine with proven activity against ZIKV. There has been no active circulation of CHIKV in Argentina in 2017. Outbreaks of CHIKV fever have a complication: the development of chronic post-disease rheumatism. There are not approved vaccines for humans nor effective antiviral therapies. The seriousness of these virosis has contributed to a rapid progress in the knowledge of the infection processes and the immune response. For now, Aedes aegypti and A. albopictus vectors continue to expand, suggesting that the vaccine will be the most effective means of controlling these viruses. Here we summarize information about these arbovirosis in Argentina and Brazil and describe advances in the development and evaluation of vaccines.

Dengue, zika, chikungunya and the development of vaccines

Directory of Open Access Journals (Sweden)

Isabel N. Kantor

2018-01-01

Full Text Available Dengue (DENV, zika (ZIKV and chikungunya (CHIKV, three arbovirosis transmitted by Aedes mosquitoes, have spread in recent decades in humid tropical and subtropical zones. Dengue is epidemic in subtropical areas of Argentina. DENV infection confers lasting immunity against the infecting serotype but increases the risk of serious disease upon reinfection by any of the other three. The recombinant tetravalent vaccine Dengvaxia® prevents severe dengue and hospitalization in seropositive subjects. In 2017, Dengvaxia was approved in Argentina, for ages 9 to 45, but is not included in the national vaccination calendar. Two other vaccines are in Phase III evaluation: one developed by NIAID / Instituto Butantan and the other by Takeda. ZIKV, a virus associated with microcephaly in newborns in Brazil, circulates since 2016 in Argentina. There is still not effective treatment nor vaccine with proven activity against ZIKV. There has been no active circulation of CHIKV in Argentina in 2017. Outbreaks of CHIKV fever have a complication: the development of chronic post-disease rheumatism. There are not approved vaccines for humans nor effective antiviral therapies. The seriousness of these virosis has contributed to a rapid progress in the knowledge of the infection processes and the immune response. For now, Aedes aegypti and A. albopictus vectors continue to expand, suggesting that the vaccine will be the most effective means of controlling these viruses. Here we summarize information about these arbovirosis in Argentina and Brazil and describe advances in the development and evaluation of vaccines.

Progress towards meningitis prevention in the conjugate vaccines era

Directory of Open Access Journals (Sweden)

Cristina Aparecida Borges Laval

Full Text Available Acute bacterial meningitis is an important cause of morbidity and mortality among children less than five years old. Haemophilus influenzae, Streptococcus pneumoniae and Neisseria meningitidis are the most important agents of bacterial meningitis in developing countries. The development of the conjugate vaccines in the beginning of the 90's, especially type b H. influenzae (Hib, and more recently the heptavalent pneumococcal and the serogroup C meningococcal vaccines, have contributed directly to changes in the epidemiological profile of these invasive diseases (direct effect and of their carriage status (indirect effect. We review the impact of the Hib conjugate vaccine in Latin American countries, where this vaccine has been implemented, and the potential of pneumococcal and meningococcal conjugate vaccines for the reduction of meningitis worldwide. We also address constraints for the development and delivery of these vaccines and review new candidate state-of-the-art vaccines. The greatest challenge, undoubtedly, is to implement these vaccines worldwide, especially in the developing regions.

Progress toward implementation of human papillomavirus vaccination--the Americas, 2006-2010.

Science.gov (United States)

2011-10-14

Cervical cancer is a major cause of morbidity and mortality in the Americas, where an estimated 80,574 new cases and 36,058 deaths were reported in 2008, with 85% of this burden occurring in Latin America and the Caribbean. Two oncogenic human papillomavirus (HPV) types (16 and 18) cause approximately 70% of cervical cancers and a substantial proportion of other HPV-related cancers. HPV vaccination provides an opportunity to greatly reduce cervical cancer burden through primary prevention of HPV infection. This report summarizes the progress toward HPV vaccine introduction in the Americas, focusing on countries that have introduced the vaccine in national or regional immunization programs. As of January 2011, four countries in the Americas had introduced HPV vaccine. Overcoming issues related to financing and delivery of HPV vaccine remains a key public health challenge to more widespread implementation of HPV vaccination in the Americas.

Clinical development of Ebola vaccines

Science.gov (United States)

Sridhar, Saranya

2015-01-01

The ongoing outbreak of Ebola virus disease in West Africa highlighted the lack of a licensed drug or vaccine to combat the disease and has renewed the urgency to develop a pipeline of Ebola vaccines. A number of different vaccine platforms are being developed by assessing preclinical efficacy in animal models and expediting clinical development. Over 15 different vaccines are in preclinical development and 8 vaccines are now in different stages of clinical evaluation. These vaccines include DNA vaccines, virus-like particles and viral vectors such as live replicating vesicular stomatitis virus (rVSV), human and chimpanzee adenovirus, and vaccinia virus. Recently, in preliminary results reported from the first phase III trial of an Ebola vaccine, the rVSV-vectored vaccine showed promising efficacy. This review charts this rapidly advancing area of research focusing on vaccines in clinical development and discusses the future opportunities and challenges faced in the licensure and deployment of Ebola vaccines. PMID:26668751

Complexity of Human Antibody Response to Dengue Virus: Implication for Vaccine Development.

Science.gov (United States)

Tsai, Wen-Yang; Lin, Hong-En; Wang, Wei-Kung

2017-01-01

The four serotypes of dengue virus (DENV) are the leading cause of arboviral diseases in humans. Decades of efforts have made remarkable progress in dengue vaccine development. Despite the first dengue vaccine (dengvaxia from Sanofi Pasteur), a live-attenuated tetravalent chimeric yellow fever-dengue vaccine, has been licensed by several countries since 2016, its overall moderate efficacy (56.5-60.8%) in the presence of neutralizing antibodies during the Phase 2b and 3 trials, lower efficacy among dengue naïve compared with dengue experienced individuals, and increased risk of hospitalization among young children during the follow-up highlight the need for a better understanding of humoral responses after natural DENV infection. Recent studies of more than 300 human monoclonal antibodies (mAbs) against DENV have led to the discovery of several novel epitopes on the envelope protein recognized by potent neutralizing mAbs. This information together with in-depth studies on polyclonal sera and B-cells following natural DENV infection has tremendous implications for better immunogen design for a safe and effective dengue vaccine. This review outlines the progress in our understanding of mouse mAbs, human mAbs, and polyclonal sera against DENV envelope and precursor membrane proteins, two surface proteins involved in vaccine development, following natural infection; analyses of these discoveries have provided valuable insight into new strategies involving molecular technology to induce more potent neutralizing antibodies and less enhancing antibodies for next-generation dengue vaccine development.

Complexity of Human Antibody Response to Dengue Virus: Implication for Vaccine Development

Directory of Open Access Journals (Sweden)

Wen-Yang Tsai

2017-07-01

Full Text Available The four serotypes of dengue virus (DENV are the leading cause of arboviral diseases in humans. Decades of efforts have made remarkable progress in dengue vaccine development. Despite the first dengue vaccine (dengvaxia from Sanofi Pasteur, a live-attenuated tetravalent chimeric yellow fever-dengue vaccine, has been licensed by several countries since 2016, its overall moderate efficacy (56.5–60.8% in the presence of neutralizing antibodies during the Phase 2b and 3 trials, lower efficacy among dengue naïve compared with dengue experienced individuals, and increased risk of hospitalization among young children during the follow-up highlight the need for a better understanding of humoral responses after natural DENV infection. Recent studies of more than 300 human monoclonal antibodies (mAbs against DENV have led to the discovery of several novel epitopes on the envelope protein recognized by potent neutralizing mAbs. This information together with in-depth studies on polyclonal sera and B-cells following natural DENV infection has tremendous implications for better immunogen design for a safe and effective dengue vaccine. This review outlines the progress in our understanding of mouse mAbs, human mAbs, and polyclonal sera against DENV envelope and precursor membrane proteins, two surface proteins involved in vaccine development, following natural infection; analyses of these discoveries have provided valuable insight into new strategies involving molecular technology to induce more potent neutralizing antibodies and less enhancing antibodies for next-generation dengue vaccine development.

Efficacy of a novel Pasteurella multocida vaccine against progressive atrophic rhinitis of swine

Science.gov (United States)

Hsuan, Shih-Ling; Liao, Chih-Ming; Huang, Chienjin; Winton, James R.; Chen, Zeng-Weng; Lee, Wei-Cheng; Liao, Jiunn-Wang; Chen, Ter-Hsin; Chiou, Chwei-Jang; Yeh, Kuang-Sheng; Chien, Maw-Sheng

2009-01-01

The efficacy of a novel vaccine composed of three short recombinant subunit Pasteurella multocida toxin (PMT) proteins in combination with a bi-valent P. multocida whole-cell bacterin (rsPMT–PM) was evaluated in field studies for prevention and control of progressive atrophic rhinitis (PAR) of swine at 15 conventional farrow-to-finish farms. Experimental piglets that were immunized twice with the rsPMT–PM vaccine developed detectable titers of neutralizing antibodies (greater than 1:8) that prevented the growth retardation and pathological lesions typically observed following challenge with authentic PMT. A total of 542 sows were vaccinated once or twice prior to parturition and serum neutralizing antibody titers were evaluated. Both single and double vaccination protocols induced neutralizing antibody titers of 1:16 or higher in 62% and 74% of sows, respectively. Notably, neither sows nor piglets at a farm experiencing a severe outbreak of PAR at the time of the vaccination trial had detectable antibody titers, but antibody titers increased significantly to 1:16 or higher in 40% of sows following double vaccination. During the year after vaccination, clinical signs of PAR decreased in fattening pigs and growth performance improved sufficiently to reduce the rearing period until marketing by 2 weeks. Collectively, these results indicate that the rsPMT–PM vaccine could be used to provide protective immunity for controlling the prevalence and severity of PAR among farm-raised swine.

[The development of therapeutic vaccine for hepatitis C virus].

Science.gov (United States)

Kimura, Kiminori; Kohara, Michinori

2012-10-01

Chronic hepatitis C caused by infection with the hepatitis C virus(HCV)is a global health problem. HCV causes persistent infection that can lead to chronic liver diseases such as chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. The therapeutic efficacy of antiviral drugs is not optimal in patients with chronic infection; furthermore, an effective vaccine has not yet been developed. To design an effective HCV vaccine, generation of a convenient animal model of HCV infection is necessary. Recently, we used the Cre/loxP switching system to generate an immunocompetent mouse model of HCV expression, thereby enabling the study of host immune responses against HCV proteins. At present vaccine has not yet been shown to be therapeutically effective against chronic HCV infection. We examined the therapeutic effects of a recombinant vaccinia virus(rVV)encoding HCV protein in a mouse model. we generated rVVs for 3 different HCV proteins and found that one of the recombinant viruses encoding a nonstructural protein(rVV-N25)resolved pathological chronic hepatitis C symptoms in the liver. We propose the possibility that rVV-N25 immunization has the potential for development of an effective therapeutic vaccine for HCV induced chronic hepatitis. The utilization of the therapeutic vaccine can protect progress to chronic hepatitis, and as a consequence, leads to eradication of hepatocellular carcinoma. In this paper, we summarized our current study for HCV therapeutic vaccine and review the vaccine development to date.

Development of an anti-HIV vaccine eliciting broadly neutralizing antibodies.

Science.gov (United States)

Ahmed, Yousuf; Tian, Meijuan; Gao, Yong

2017-09-12

The extreme HIV diversity posts a great challenge on development of an effective anti-HIV vaccine. To solve this problem, it is crucial to discover an appropriate immunogens and strategies that are able to prevent the transmission of the diverse viruses that are circulating in the world. Even though there have been a number of broadly neutralizing anti-HIV antibodies (bNAbs) been discovered in recent years, induction of such antibodies to date has only been observed in HIV-1 infection. Here, in this mini review, we review the progress in development of HIV vaccine in eliciting broad immune response, especially production of bNAbs, discuss possible strategies, such as polyvalent sequential vaccination, that facilitates B cell maturation leading to bNAb response.

Establishing the pig as a large animal model for vaccine development against human cancer

DEFF Research Database (Denmark)

Overgaard, Nana Haahr; Frøsig, Thomas Mørch; Welner, Simon

2015-01-01

Immunotherapy has increased overall survival of metastatic cancer patients, and cancer antigens are promising vaccine targets. To fulfill the promise, appropriate tailoring of the vaccine formulations to mount in vivo cytotoxic T cell (CTL) responses toward co-delivered cancer antigens is essential...... and the porcine immunome is closer related to the human counterpart, we here introduce pigs as a supplementary large animal model for human cancer vaccine development. IDO and RhoC, both important in human cancer development and progression, were used as vaccine targets and 12 pigs were immunized with overlapping......C-derived peptides across all groups with no adjuvant being superior. These findings support the further use of pigs as a large animal model for vaccine development against human cancer....

Progress and novel strategies in vaccine development and treatment of anthrax.

Science.gov (United States)

Chitlaru, Theodor; Altboum, Zeev; Reuveny, Shaul; Shafferman, Avigdor

2011-01-01

The lethal anthrax disease is caused by spores of the gram-positive Bacillus anthracis, a member of the cereus group of bacilli. Although the disease is very rare in the Western world, development of anthrax countermeasures gains increasing attention due to the potential use of B. anthracis spores as a bio-terror weapon. Protective antigen (PA), the non-toxic subunit of the bacterial secreted exotoxin, fulfills the role of recognizing a specific receptor and mediating the entry of the toxin into the host target cells. PA elicits a protective immune response and represents the basis for all current anthrax vaccines. Anti-PA neutralizing antibodies are useful correlates for protection and for vaccine efficacy evaluation. Post exposure anti-toxemic and anti-bacteremic prophylactic treatment of anthrax requires prolonged antibiotic administration. Shorter efficient postexposure treatments may require active or passive immunization, in addition to antibiotics. Although anthrax is acknowledged as a toxinogenic disease, additional factors, other than the bacterial toxin, may be involved in the virulence of B. anthracis and may be needed for the long-lasting protection conferred by PA immunization. The search for such novel factors is the focus of several high throughput genomic and proteomic studies that are already leading to identification of novel targets for therapeutics, for vaccine candidates, as well as biomarkers for detection and diagnosis. © 2010 John Wiley & Sons A/S.

Vaccine development for syphilis.

Science.gov (United States)

Lithgow, Karen V; Cameron, Caroline E

2017-01-01

Syphilis, caused by the spirochete Treponema pallidum subspecies pallidum, continues to be a globally prevalent disease despite remaining susceptible to penicillin treatment. Syphilis vaccine development is a viable preventative approach that will serve to complement public health-oriented syphilis prevention, screening and treatment initiatives to deliver a two-pronged approach to stemming disease spread worldwide. Areas covered: This article provides an overview of the need for development of a syphilis vaccine, summarizes significant information that has been garnered from prior syphilis vaccine studies, discusses the critical aspects of infection that would have to be targeted by a syphilis vaccine, and presents the current understanding within the field of the correlates of protection needed to be achieved through vaccination. Expert commentary: Syphilis vaccine development should be considered a priority by industry, regulatory and funding agencies, and should be appropriately promoted and supported.

Sustainable vaccine development: a vaccine manufacturer's perspective.

Science.gov (United States)

Rappuoli, Rino; Hanon, Emmanuel

2018-05-08

Vaccination remains the most cost-effective public health intervention after clean water, and the benefits impressively outweigh the costs. The efforts needed to fulfill the steadily growing demands for next-generation and novel vaccines designed for emerging pathogens and new indications are only realizable in a sustainable business model. Vaccine development can be fast-tracked through strengthening international collaborations, and the continuous innovation of technologies to accelerate their design, development, and manufacturing. However, these processes should be supported by a balanced project portfolio, and by managing sustainable vaccine procurement strategies for different types of markets. Collectively this will allow a gradual shift to a more streamlined and profitable vaccine production, which can significantly contribute to the worldwide effort to shape global health. Copyright © 2018 GlaxoSmithKine Biologicals SA. Published by Elsevier Ltd.. All rights reserved.

New developments and concepts related to biomarker application to vaccines

Science.gov (United States)

Ahmed, S. Sohail; Black, Steve; Ulmer, Jeffrey

2012-01-01

Summary This minireview will provide a perspective on new developments and concepts related to biomarker applications for vaccines. In the context of preventive vaccines, biomarkers have the potential to predict adverse events in select subjects due to differences in genetic make‐up/underlying medical conditions or to predict effectiveness (good versus poor response). When expanding them to therapeutic vaccines, their utility in identification of patients most likely to respond favourably (or avoid potentially negative effects of treatment) becomes self‐explanatory. Despite the progress made so far on dissection of various pathways of biological significance in humans, there is still plenty to unravel about the mysteries related to the quantitative and qualitative aspects of the human host response. This review will provide a focused overview of new concepts and developments in the field of vaccine biomarkers including (i) vaccine‐dependent signatures predicting subject response and safety, (ii) predicting therapeutic vaccine efficacy in chronic diseases, (iii) exploring the genetic make‐up of the host that may modulate subject‐specific adverse events or affect the quality of immune responses, and (iv) the topic of volunteer stratification as a result of biomarker screening (e.g. for therapeutic vaccines but also potentially for preventive vaccines) or as a reflection of an effort to compare select groups (e.g. vaccinated subjects versus patients recovering from infection) to enable the discovery of clinically relevant biomarkers for preventive vaccines. PMID:21895991

Review Article: Prospect and Progress of Malaria Vaccine ...

African Journals Online (AJOL)

Malaria kills one child every 30 seconds in Africa. The development of a safe vaccine remains an urgent unmet need which could greatly control and even lead to the eradication of the disease. The success recorded in the recent vaccine trials have given some ray of hope that a safe and effective vaccine against malaria will ...

Development of Antibody-Based Vaccines Targeting the Tumor Vasculature.

Science.gov (United States)

Zhuang, Xiaodong; Bicknell, Roy

2016-01-01

A functional vasculature is essential for tumor progression and malignant cell metastasis. Endothelial cells lining blood vessels in the tumor are exposed to a unique microenvironment, which in turn induces expression of specific proteins designated as tumor endothelial markers (TEMs). TEMs either localized at the plasma membrane or secreted into the extracellular matrix are accessible for antibody targeting, which can be either infused or generated de novo via vaccination. Recent studies have demonstrated vaccines against several TEMs can induce a strong antibody response accompanied by a potent antitumor effect in animal models. These findings present an exciting field for novel anticancer therapy development. As most of the TEMs are self-antigens, breaking tolerance is necessary for a successful vaccine. This chapter describes approaches to efficiently induce a robust antibody response against the tumor vasculature.

Multi-stage subunit vaccine development against Mycobacterium paratuberculosis and Johne’s disease in ruminants

DEFF Research Database (Denmark)

Jungersen, Gregers

paratuberculosis provide only partial protection and interfere with diagnostic tests for JD and surveillance for bovine TB. In contrast, recombinant subunit vaccines can be designed to be used without compromising control of bTB and Map. Taking advantage of data from mouse TB studies, and early Map vaccination...... in macrophages. The disease progression is very slow with neonatal animals being the most susceptible to infection, but without development of detectable IFN-γ responses for months after infection and rarely with clinical disease before the second or third year of life. Available whole cell vaccines against......- and field-studies we developed a vaccine with a single recombinant fusion protein comprising four acute-stage antigens (Ags) and one latent-stage Ag formulated in adjuvant (FET-vaccine). In post-exposure vaccination of calves and goats with necropsy 8-12 months post inoculation, we determined...

Development of a metabolically active, non-replicating sporozoite vaccine to prevent Plasmodium falciparum malaria.

Science.gov (United States)

Hoffman, Stephen L; Billingsley, Peter F; James, Eric; Richman, Adam; Loyevsky, Mark; Li, Tao; Chakravarty, Sumana; Gunasekera, Anusha; Chattopadhyay, Rana; Li, Minglin; Stafford, Richard; Ahumada, Adriana; Epstein, Judith E; Sedegah, Martha; Reyes, Sharina; Richie, Thomas L; Lyke, Kirsten E; Edelman, Robert; Laurens, Matthew B; Plowe, Christopher V; Sim, B Kim Lee

2010-01-01

Immunization of volunteers by the bite of mosquitoes carrying radiation-attenuated Plasmodium falciparum sporozoites protects greater than 90% of such volunteers against malaria, if adequate numbers of immunizing biting sessions and sporozoite-infected mosquitoes are used. Nonetheless, until recently it was considered impossible to develop, license and commercialize a live, whole parasite P. falciparum sporozoite (PfSPZ) vaccine. In 2003 Sanaria scientists reappraised the potential impact of a metabolically active, non-replicating PfSPZ vaccine, and outlined the challenges to producing such a vaccine. Six years later, significant progress has been made in overcoming these challenges. This progress has enabled the manufacture and release of multiple clinical lots of a 1(st) generation metabolically active, non-replicating PfSPZ vaccine, the Sanaria PfSPZ Vaccine, submission of a successful Investigational New Drug application to the US Food and Drug Administration, and initiation of safety, immunogenicity and protective efficacy studies in volunteers in MD, US. Efforts are now focused on how best to achieve submission of a successful Biologics License Application and introduce the vaccine to the primary target population of African children in the shortest possible period of time. This will require implementation of a systematic, efficient clinical development plan. Short term challenges include optimizing the (1) efficiency and scale up of the manufacturing process and quality control assays, (2) dosage regimen and method of administration, (3) potency of the vaccine, and (4) logistics of delivering the vaccine to those who need it most, and finalizing the methods for vaccine stabilization and attenuation. A medium term goal is to design and build a facility for manufacturing highly potent and stable vaccine for pivotal Phase 3 studies and commercial launch.

Human capital gaps in vaccine development: an issue for global vaccine development and global health.

Science.gov (United States)

Cawein, Andrea; Emini, Emilio; Watson, Michael; Dailey, Joanna; Donnelly, John; Tresnan, Dina; Evans, Tom; Plotkin, Stanley; Gruber, William

2017-05-01

Despite the success of vaccines in reducing the morbidity and mortality associated with infectious diseases, many infectious diseases, both newly emerging and well known, lack vaccines. The global capability for beginning-to-end vaccine development has become limited, primarily owing to a scarcity of human capital necessary to guide the development of novel vaccines from the laboratory to the marketplace. Here, we identify and discuss the gaps in human capital necessary for robust vaccine development and make recommendations to begin to address these deficiencies. © 2017 New York Academy of Sciences.

Current strategic thinking for the development of a trivalent alphavirus vaccine for human use.

Science.gov (United States)

Wolfe, Daniel N; Heppner, D Gray; Gardner, Shea N; Jaing, Crystal; Dupuy, Lesley C; Schmaljohn, Connie S; Carlton, Kevin

2014-09-01

Vaccinations against the encephalitic alphaviruses (western, eastern, and Venezuelan equine encephalitis virus) are of significant interest to biological defense, public health, and agricultural communities alike. Although vaccines licensed for veterinary applications are used in the Western Hemisphere and attenuated or inactivated viruses have been used under Investigational New Drug status to protect at-risk personnel, there are currently no licensed vaccines for use in humans. Here, we will discuss the need for a trivalent vaccine that can protect humans against all three viruses, recent progress to such a vaccine, and a strategy to continue development to Food and Drug Administration licensure. © The American Society of Tropical Medicine and Hygiene.

A brief history of the global effort to develop a preventive HIV vaccine.

Science.gov (United States)

Esparza, José

2013-08-02

Soon after HIV was discovered as the cause of AIDS in 1983-1984, there was an expectation that a preventive vaccine would be rapidly developed. In trying to achieve that goal, three successive scientific paradigms have been explored: induction of neutralizing antibodies, induction of cell mediated immunity, and exploration of combination approaches and novel concepts. Although major progress has been made in understanding the scientific basis for HIV vaccine development, efficacy trials have been critical in moving the field forward. In 2009, the field was reinvigorated with the modest results obtained from the RV144 trial conducted in Thailand. Here, we review those vaccine development efforts, with an emphasis on events that occurred during the earlier years. The goal is to provide younger generations of scientists with information and inspiration to continue the search for an HIV vaccine. Copyright © 2013 The Author. Published by Elsevier Ltd.. All rights reserved.

Ebolavirus Vaccines: Progress in the Fight Against Ebola Virus Disease

Directory of Open Access Journals (Sweden)

Xiao-Xin Wu

2015-11-01

Full Text Available Ebolaviruses are highly infectious pathogens that cause lethal Ebola virus disease (EVD in humans and non-human primates (NHPs. Due to their high pathogenicity and transmissibility, as well as the potential to be misused as a bioterrorism agent, ebolaviruses would threaten the health of global populations if not controlled. In this review, we describe the origin and structure of ebolaviruses and the development of vaccines from the beginning of the 1980s, including conventional ebolavirus vaccines, DNA vaccines, Ebola virus-like particles (VLPs, vaccinia virus-based vaccines, Venezuelan equine encephalitis virus (VEEV-like replicon particles, Kunjin virus-based vaccine, recombinant Zaire Ebolavirus∆VP30, recombinant cytomegalovirus (CMV-based vaccines, recombinant rabies virus (RABV-based vaccines, recombinant paramyxovirus-based vaccines, adenovirus-based vaccines and vesicular stomatitis virus (VSV-based vaccines. No licensed vaccine or specific treatment is currently available to counteract ebolavirus infection, although DNA plasmids and several viral vector approaches have been evaluated as promising vaccine platforms. These vaccine candidates have been confirmed to be successful in protecting NHPs against lethal infection. Moreover, these vaccine candidates were successfully advanced to clinical trials. The present review provides an update of the current research on Ebola vaccines, with the aim of providing an overview on current prospects in the fight against EVD.

[Development of new vaccines].

Science.gov (United States)

González-Romo, Fernando; Picazo, Juan J

2015-10-01

Recent and important advances in the fields of immunology, genomics, functional genomics, immunogenetics, immunogenomics, bioinformatics, microbiology, genetic engineering, systems biology, synthetic biochemistry, proteomics, metabolomics and nanotechnology, among others, have led to new approaches in the development of vaccines. The better identification of ideal epitopes, the strengthening of the immune response due to new adjuvants, and the search of new routes of vaccine administration, are good examples of advances that are already a reality and that will favour the development of more vaccines, their use in indicated population groups, or its production at a lower cost. There are currently more than 130 vaccines are under development against the more wished (malaria or HIV), difficult to get (CMV or RSV), severe re-emerging (Dengue or Ebola), increasing importance (Chagas disease or Leishmania), and nosocomial emerging (Clostridium difficile or Staphylococcus aureus) infectious diseases. Copyright © 2015. Published by Elsevier España, S.L.U.

Accelerating the development of a therapeutic vaccine for human Chagas disease: rationale and prospects.

Science.gov (United States)

Dumonteil, Eric; Bottazzi, Maria Elena; Zhan, Bin; Heffernan, Michael J; Jones, Kathryn; Valenzuela, Jesus G; Kamhawi, Shaden; Ortega, Jaime; de Leon Rosales, Samuel Ponce; Lee, Bruce Y; Bacon, Kristina M; Fleischer, Bernhard; Slingsby, B T; Cravioto, Miguel Betancourt; Tapia-Conyer, Roberto; Hotez, Peter J

2012-09-01

Chagas disease is a leading cause of heart disease affecting approximately 10 million people in Latin America and elsewhere worldwide. The two major drugs available for the treatment of Chagas disease have limited efficacy in Trypanosoma cruzi-infected adults with indeterminate (patients who have seroconverted but do not yet show signs or symptoms) and determinate (patients who have both seroconverted and have clinical disease) status; they require prolonged treatment courses and are poorly tolerated and expensive. As an alternative to chemotherapy, an injectable therapeutic Chagas disease vaccine is under development to prevent or delay Chagasic cardiomyopathy in patients with indeterminate or determinate status. The bivalent vaccine will be comprised of two recombinant T. cruzi antigens, Tc24 and TSA-1, formulated on alum together with the Toll-like receptor 4 agonist, E6020. Proof-of-concept for the efficacy of these antigens was obtained in preclinical testing at the Autonomous University of Yucatan. Here the authors discuss the potential for a therapeutic Chagas vaccine as well as the progress made towards such a vaccine, and the authors articulate a roadmap for the development of the vaccine as planned by the nonprofit Sabin Vaccine Institute Product Development Partnership and Texas Children's Hospital Center for Vaccine Development in collaboration with an international consortium of academic and industrial partners in Mexico, Germany, Japan, and the USA.

Ebolavirus Vaccines: Progress in the Fight Against Ebola Virus Disease.

Science.gov (United States)

Wu, Xiao-Xin; Yao, Hang-Ping; Wu, Nan-Ping; Gao, Hai-Nv; Wu, Hai-Bo; Jin, Chang-Zhong; Lu, Xiang-Yun; Xie, Tian-Shen; Li, Lan-Juan

2015-01-01

Ebolaviruses are highly infectious pathogens that cause lethal Ebola virus disease (EVD) in humans and non-human primates (NHPs). Due to their high pathogenicity and transmissibility, as well as the potential to be misused as a bioterrorism agent, ebolaviruses would threaten the health of global populations if not controlled. In this review, we describe the origin and structure of ebolaviruses and the development of vaccines from the beginning of the 1980s, including conventional ebolavirus vaccines, DNA vaccines, Ebola virus-like particles (VLPs), vaccinia virus-based vaccines, Venezuelan equine encephalitis virus (VEEV)-like replicon particles, Kunjin virus-based vaccine, recombinant Zaire Ebolavirusx2206;VP30, recombinant cytomegalovirus (CMV)-based vaccines, recombinant rabies virus (RABV)-based vaccines, recombinant paramyxovirus-based vaccines, adenovirus-based vaccines and vesicular stomatitis virus (VSV)-based vaccines. No licensed vaccine or specific treatment is currently available to counteract ebolavirus infection, although DNA plasmids and several viral vector approaches have been evaluated as promising vaccine platforms. These vaccine candidates have been confirmed to be successful in protecting NHPs against lethal infection. Moreover, these vaccine candidates were successfully advanced to clinical trials. The present review provides an update of the current research on Ebola vaccines, with the aim of providing an overview on current prospects in the fight against EVD. © 2015 The Author(s) Published by S. Karger AG, Basel.

Towards clinical development of a Pfs48/45-based transmission blocking malaria vaccine

DEFF Research Database (Denmark)

Theisen, Michael; Jore, Matthijs M; Sauerwein, Robert

2017-01-01

: PubMed was searched to review the progress and future prospects for clinical development of a Pfs48/45-based subunit vaccine. We will focus on biological function, naturally acquired immunity, functional activity of specific antibodies, sequence diversity, production of recombinant protein...

Development of malaria transmission-blocking vaccines: from concept to product.

Science.gov (United States)

Wu, Yimin; Sinden, Robert E; Churcher, Thomas S; Tsuboi, Takafumi; Yusibov, Vidadi

2015-06-01

Despite decades of effort battling against malaria, the disease is still a major cause of morbidity and mortality. Transmission-blocking vaccines (TBVs) that target sexual stage parasite development could be an integral part of measures for malaria elimination. In the 1950s, Huff et al. first demonstrated the induction of transmission-blocking immunity in chickens by repeated immunizations with Plasmodium gallinaceum-infected red blood cells. Since then, significant progress has been made in identification of parasite antigens responsible for transmission-blocking activity. Recombinant technologies accelerated evaluation of these antigens as vaccine candidates, and it is possible to induce effective transmission-blocking immunity in humans both by natural infection and now by immunization with recombinant vaccines. This chapter reviews the efforts to produce TBVs, summarizes the current status and advances and discusses the remaining challenges and approaches. Copyright © 2015 Elsevier Ltd. All rights reserved.

Quality vaccines for all people: Report on the 16th annual general meeting of the Developing Countries Vaccine Manufacturers' Network, 05-07th October 2015, Bangkok, Thailand.

Science.gov (United States)

Pagliusi, Sonia; Ting, Ching-Chia; Khomvilai, Sumana

2016-06-30

The Developing Countries Vaccine Manufacturers Network (DCVMN) assembled high-profile leaders from global health organisations and vaccine manufactures for its 16th Annual General Meeting to work towards a common goal: providing quality vaccines for all people. Vaccines contribute to a healthy community and robust health system; the Ebola outbreak has raised awareness of the threat and damage one single infectious disease can make, and it is clear that the world was not prepared. However, more research to better understand emerging infectious agents might lead to suitable vaccines which help prevent future outbreaks. DCVMN members presented their progress in developing novel vaccines against Dengue, HPV, Chikungunya, Cholera, cell-based influenza and other vaccines, demonstrating the commitment towards eliminating and eradicating preventable diseases worldwide through global collaboration and technology transfer. The successful introduction of novel Sabin-IPV and Oral Cholera vaccine in China and Korea respectively in 2015 was highlighted. In order to achieve global immunisation, local authorities and community leaders play an important role in the decision-making in vaccine introduction and uptake, based on the ability of vaccines to protect vaccinated people and protect non-vaccinated in the community through herd immunity. Reducing the risk of vaccine shortages can also be achieved by increasing regulatory convergence at regional and international levels. Combatting preventable diseases remains challenging, and collective efforts for improving multi-centre clinical trials, creating regional vaccine security strategies, fostering developing vaccine markets and procurement, and building trust in vaccines were discussed. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Collaborative vaccine development: partnering pays.

Science.gov (United States)

Ramachandra, Rangappa

2008-01-01

Vaccine development, supported by infusions of public and private venture capital, is re-entering a golden age as one of the fastest growing sectors in the life-sciences industry. Demand is driven by great unmet need in underdeveloped countries, increased resistance to current treatments, bioterrorism, and for prevention indications in travelers, pediatric, and adult diseases. Production systems are becoming less reliant on processes such as egg-based manufacturing, while new processes can help to optimize vaccines. Expeditious development hinges on efficient study conduct, which is greatly enhanced through research partnerships with specialized contract research organizations (CROs) that are licensed and knowledgeable in the intricacies of immunology and with the technologic and scientific foundation to support changing timelines and strategies inherent to vaccine development. The CRO often brings a more objective assessment for probability of success and may offer alternative development pathways. Vaccine developers are afforded more flexibility and are free to focus on innovation and internal core competencies. Functions readily outsourced to a competent partner include animal model development, safety and efficacy studies, immunotoxicity and immunogenicity, dose response studies, and stability and potency testing. These functions capitalize on the CRO partner's regulatory and scientific talent and expertise, and reduce infrastructure expenses for the vaccine developer. Successful partnerships result in development efficiencies, elimination or reduced redundancies, and improved time to market. Keys to success include honest communications, transparency, and flexibility.

Which Dengue Vaccine Approach Is the Most Promising, and Should We Be Concerned about Enhanced Disease after Vaccination? The Challenges of a Dengue Vaccine.

Science.gov (United States)

Screaton, Gavin; Mongkolsapaya, Juthathip

2017-07-17

A dengue vaccine has been pursued for more than 50 years and, unlike other flaviviral vaccines such as that against yellow fever, progress has been slow. In this review, we describe progress toward the first licensed dengue vaccine Dengvaxia, which does not give complete protection against disease. The antibody response to the dengue virion is reviewed, highlighting immunodominant yet poorly neutralizing responses in the context of a highly dynamic structurally flexible dengue virus particle. Finally, we review recent evidence for cross-reactivity between antibody responses to Zika and dengue viruses, which may further complicate the development of broadly protective dengue virus vaccines. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

Recent advances in the development of vaccines for Ebola virus disease.

Science.gov (United States)

Ohimain, Elijah Ige

2016-01-04

Ebola virus is one of the most dangerous microorganisms in the world causing hemorrhagic fevers in humans and non-human primates. Ebola virus (EBOV) is a zoonotic infection, which emerges and re-emerges in human populations. The 2014 outbreak was caused by the Zaire strain, which has a kill rate of up to 90%, though 40% was recorded in the current outbreak. The 2014 outbreak is larger than all 20 outbreaks that have occurred since 1976, when the virus was first discovered. It is the first time that the virus was sustained in urban centers and spread beyond Africa into Europe and USA. Thus far, over 22,000 cases have been reported with about 50% mortality in one year. There are currently no approved therapeutics and preventive vaccines against Ebola virus disease (EVD). Responding to the devastating effe1cts of the 2014 outbreak and the potential risk of global spread, has spurred research for the development of therapeutics and vaccines. This review is therefore aimed at presenting the progress of vaccine development. Results showed that conventional inactivated vaccines produced from EBOV by heat, formalin or gamma irradiation appear to be ineffective. However, novel vaccines production techniques have emerged leading to the production of candidate vaccines that have been demonstrated to be effective in preclinical trials using small animal and non-human primates (NHP) models. Some of the promising vaccines have undergone phase 1 clinical trials, which demonstrated their safety and immunogenicity. Many of the candidate vaccines are vector based such as Vesicular Stomatitis Virus (VSV), Rabies Virus (RABV), Adenovirus (Ad), Modified Vaccinia Ankara (MVA), Cytomegalovirus (CMV), human parainfluenza virus type 3 (HPIV3) and Venezuelan Equine Encephalitis Virus (VEEV). Other platforms include virus like particle (VLP), DNA and subunit vaccines. Copyright © 2015 Elsevier B.V. All rights reserved.

Vaccine Development against Zoonotic Hepatitis E Virus: Open Questions and Remaining Challenges

Directory of Open Access Journals (Sweden)

Yuchen Nan

2018-02-01

Full Text Available Hepatitis E virus (HEV is a fecal-orally transmitted foodborne viral pathogen that causes acute hepatitis in humans and is responsible for hepatitis E outbreaks worldwide. Since the discovery of HEV as a zoonotic agent, this virus has been isolated from a variety of hosts with an ever-expanding host range. Recently, a subunit HEV vaccine developed for the prevention of human disease was approved in China, but is not yet available to the rest of the world. Meanwhile, notable progress and knowledge has been made and revealed in recent years to better understand HEV biology and infection, including discoveries of quasi-enveloped HEV virions and of a new function of the HEV-ORF3 product. However, the impact of these new findings on the development of a protective vaccine against zoonotic HEV infection requires further discussion. In this review, hallmark characteristics of HEV zoonosis, the history of HEV vaccine development, and recent discoveries in HEV virology are described. Moreover, special attention is focused on quasi-enveloped HEV virions and the potential role of the HEV-ORF3 product as antibody-neutralization target on the surface of quasi-enveloped HEV virions to provide new insights for the future development of improved vaccines against zoonotic HEV infection.

Vaccine Development against Zoonotic Hepatitis E Virus: Open Questions and Remaining Challenges

Science.gov (United States)

Nan, Yuchen; Wu, Chunyan; Zhao, Qin; Sun, Yani; Zhang, Yan-Jin; Zhou, En-Min

2018-01-01

Hepatitis E virus (HEV) is a fecal-orally transmitted foodborne viral pathogen that causes acute hepatitis in humans and is responsible for hepatitis E outbreaks worldwide. Since the discovery of HEV as a zoonotic agent, this virus has been isolated from a variety of hosts with an ever-expanding host range. Recently, a subunit HEV vaccine developed for the prevention of human disease was approved in China, but is not yet available to the rest of the world. Meanwhile, notable progress and knowledge has been made and revealed in recent years to better understand HEV biology and infection, including discoveries of quasi-enveloped HEV virions and of a new function of the HEV-ORF3 product. However, the impact of these new findings on the development of a protective vaccine against zoonotic HEV infection requires further discussion. In this review, hallmark characteristics of HEV zoonosis, the history of HEV vaccine development, and recent discoveries in HEV virology are described. Moreover, special attention is focused on quasi-enveloped HEV virions and the potential role of the HEV-ORF3 product as antibody-neutralization target on the surface of quasi-enveloped HEV virions to provide new insights for the future development of improved vaccines against zoonotic HEV infection. PMID:29520257

Application of radiation technology in vaccines development.

Science.gov (United States)

Seo, Ho Seong

2015-07-01

One of the earliest methods used in the manufacture of stable and safe vaccines is the use of chemical and physical treatments to produce inactivated forms of pathogens. Although these types of vaccines have been successful in eliciting specific humoral immune responses to pathogen-associated immunogens, there is a large demand for the development of fast, safe, and effective vaccine manufacturing strategies. Radiation sterilization has been used to develop a variety of vaccine types, because it can eradicate chemical contaminants and penetrate pathogens to destroy nucleic acids without damaging the pathogen surface antigens. Nevertheless, irradiated vaccines have not widely been used at an industrial level because of difficulties obtaining the necessary equipment. Recent successful clinical trials of irradiated vaccines against pathogens and tumors have led to a reevaluation of radiation technology as an alternative method to produce vaccines. In the present article, we review the challenges associated with creating irradiated vaccines and discuss potential strategies for developing vaccines using radiation technology.

Model for product development of vaccines against neglected tropical diseases: a vaccine against human hookworm.

Science.gov (United States)

Bottazzi, Maria Elena; Brown, Ami Shah

2008-12-01

This article provides an overview of the advances in product development and technology transfer of the vaccine against human hookworm, with particular emphasis on the lessons learned and the challenges of developing a vaccine in the nonprofit sector. The comprehensive approach to vaccine development established by the Human Hookworm Vaccine Initiative (HHVI) identifies key operational and technical aspects that are essential for a successful partnership with a developing country vaccine manufacturer. This article also highlights the importance of a global access roadmap to guide the vaccine development program. The advancement of new products for the control of neglected tropical diseases portends great challenges for global access, including aspects related to vaccine design, product development and manufacture, vaccine introduction and distribution, financing, knowledge dissemination and intellectual property management. With only three vaccines for neglected tropical diseases in clinical trials - hookworm, leishmaniasis and schistosomiasis - we are at the nascent stages of developing vaccines for neglected populations. Product development public-private partnerships, such as the HHVI, continue to show great promise on this front and will eventually provide significant control tools for achieving millennium development goals related to poverty reduction, as well as child and maternal health.

VaxCelerate II: rapid development of a self-assembling vaccine for Lassa fever.

Science.gov (United States)

Leblanc, Pierre; Moise, Leonard; Luza, Cybelle; Chantaralawan, Kanawat; Lezeau, Lynchy; Yuan, Jianping; Field, Mary; Richer, Daniel; Boyle, Christine; Martin, William D; Fishman, Jordan B; Berg, Eric A; Baker, David; Zeigler, Brandon; Mais, Dale E; Taylor, William; Coleman, Russell; Warren, H Shaw; Gelfand, Jeffrey A; De Groot, Anne S; Brauns, Timothy; Poznansky, Mark C

2014-01-01

Development of effective vaccines against emerging infectious diseases (EID) can take as much or more than a decade to progress from pathogen isolation/identification to clinical approval. As a result, conventional approaches fail to produce field-ready vaccines before the EID has spread extensively. Lassa is a prototypical emerging infectious disease endemic to West Africa for which no successful vaccine is available. We established the VaxCelerate Consortium to address the need for more rapid vaccine development by creating a platform capable of generating and pre-clinically testing a new vaccine against specific pathogen targets in less than 120 d A self-assembling vaccine is at the core of the approach. It consists of a fusion protein composed of the immunostimulatory Mycobacterium tuberculosis heat shock protein 70 (MtbHSP70) and the biotin binding protein, avidin. Mixing the resulting protein (MAV) with biotinylated pathogen-specific immunogenic peptides yields a self-assembled vaccine (SAV). To meet the time constraint imposed on this project, we used a distributed R&D model involving experts in the fields of protein engineering and production, bioinformatics, peptide synthesis/design and GMP/GLP manufacturing and testing standards. SAV immunogenicity was first tested using H1N1 influenza specific peptides and the entire VaxCelerate process was then tested in a mock live-fire exercise targeting Lassa fever virus. We demonstrated that the Lassa fever vaccine induced significantly increased class II peptide specific interferon-γ CD4(+) T cell responses in HLA-DR3 transgenic mice compared to peptide or MAV alone controls. We thereby demonstrated that our SAV in combination with a distributed development model may facilitate accelerated regulatory review by using an identical design for each vaccine and by applying safety and efficacy assessment tools that are more relevant to human vaccine responses than current animal models.

Status of vaccine research and development of vaccines for herpes simplex virus.

Science.gov (United States)

Johnston, Christine; Gottlieb, Sami L; Wald, Anna

2016-06-03

Herpes simplex virus type-1 (HSV-1) and -2 (HSV-2) are highly prevalent global pathogens which commonly cause recurrent oral and genital ulcerations. Less common but more serious complications include meningitis, encephalitis, neonatal infection, and keratitis. HSV-2 infection is a significant driver of the HIV epidemic, increasing the risk of HIV acquisition 3 fold. As current control strategies for genital HSV-2 infection, including antiviral therapy and condom use, are only partially effective, vaccines will be required to reduce infection. Both preventive and therapeutic vaccines for HSV-2 are being pursued and are in various stages of development. We will provide an overview of efforts to develop HSV-2 vaccines, including a discussion of the clinical need for an HSV vaccine, and status of research and development with an emphasis on recent insights from trials of vaccine candidates in clinical testing. In addition, we will touch upon aspects of HSV vaccine development relevant to low and middle income countries. Copyright © 2016 World Health Organization. Published by Elsevier Ltd.. All rights reserved.

Advances and challenges in malaria vaccine development.

Science.gov (United States)

Crompton, Peter D; Pierce, Susan K; Miller, Louis H

2010-12-01

Malaria caused by Plasmodium falciparum remains a major public health threat, especially among children and pregnant women in Africa. An effective malaria vaccine would be a valuable tool to reduce the disease burden and could contribute to elimination of malaria in some regions of the world. Current malaria vaccine candidates are directed against human and mosquito stages of the parasite life cycle, but thus far, relatively few proteins have been studied for potential vaccine development. The most advanced vaccine candidate, RTS,S, conferred partial protection against malaria in phase II clinical trials and is currently being evaluated in a phase III trial in Africa. New vaccine targets need to be identified to improve the chances of developing a highly effective malaria vaccine. A better understanding of the mechanisms of naturally acquired immunity to malaria may lead to insights for vaccine development.

Recent progress and future directions for reduction, refinement, and replacement of animal use in veterinary vaccine potency and safety testing: a report from the 2010 NICEATM-ICCVAM International Vaccine Workshop.

Science.gov (United States)

Stokes, W S; Kulpa-Eddy, J; Brown, K; Srinivas, G; McFarland, R

2012-01-01

Veterinary vaccines contribute to improved animal and human health and welfare by preventing infectious diseases. However, testing necessary to ensure vaccine effectiveness and safety can involve large numbers of animals and significant pain and distress. NICEATM and ICCVAM recently convened an international workshop to review the state of the science of human and veterinary vaccine potency and safety testing, and to identify priority activities to advance new and improved methods that can further reduce, refine and replace animal use. Rabies, Clostridium sp., and Leptospira sp. vaccines were identified as the highest priorities, while tests requiring live viruses and bacteria hazardous to laboratory workers, livestock, pets, and wildlife were also considered high priorities. Priority research, development and validation activities to address critical knowledge and data gaps were identified, including opportunities to apply new science and technology. Enhanced international harmonization and cooperation and closer collaborations between human and veterinary researchers were recommended to expedite progress. Implementation of the workshop recommendations is expected to advance new methods for vaccine testing that will benefit animal welfare and ensure continued and improved protection of human and animal health.

Vaxjo: A Web-Based Vaccine Adjuvant Database and Its Application for Analysis of Vaccine Adjuvants and Their Uses in Vaccine Development

Directory of Open Access Journals (Sweden)

Samantha Sayers

2012-01-01

Full Text Available Vaccine adjuvants are compounds that enhance host immune responses to co-administered antigens in vaccines. Vaxjo is a web-based central database and analysis system that curates, stores, and analyzes vaccine adjuvants and their usages in vaccine development. Basic information of a vaccine adjuvant stored in Vaxjo includes adjuvant name, components, structure, appearance, storage, preparation, function, safety, and vaccines that use this adjuvant. Reliable references are curated and cited. Bioinformatics scripts are developed and used to link vaccine adjuvants to different adjuvanted vaccines stored in the general VIOLIN vaccine database. Presently, 103 vaccine adjuvants have been curated in Vaxjo. Among these adjuvants, 98 have been used in 384 vaccines stored in VIOLIN against over 81 pathogens, cancers, or allergies. All these vaccine adjuvants are categorized and analyzed based on adjuvant types, pathogens used, and vaccine types. As a use case study of vaccine adjuvants in infectious disease vaccines, the adjuvants used in Brucella vaccines are specifically analyzed. A user-friendly web query and visualization interface is developed for interactive vaccine adjuvant search. To support data exchange, the information of vaccine adjuvants is stored in the Vaccine Ontology (VO in the Web Ontology Language (OWL format.

Vaxjo: a web-based vaccine adjuvant database and its application for analysis of vaccine adjuvants and their uses in vaccine development.

Science.gov (United States)

Sayers, Samantha; Ulysse, Guerlain; Xiang, Zuoshuang; He, Yongqun

2012-01-01

Vaccine adjuvants are compounds that enhance host immune responses to co-administered antigens in vaccines. Vaxjo is a web-based central database and analysis system that curates, stores, and analyzes vaccine adjuvants and their usages in vaccine development. Basic information of a vaccine adjuvant stored in Vaxjo includes adjuvant name, components, structure, appearance, storage, preparation, function, safety, and vaccines that use this adjuvant. Reliable references are curated and cited. Bioinformatics scripts are developed and used to link vaccine adjuvants to different adjuvanted vaccines stored in the general VIOLIN vaccine database. Presently, 103 vaccine adjuvants have been curated in Vaxjo. Among these adjuvants, 98 have been used in 384 vaccines stored in VIOLIN against over 81 pathogens, cancers, or allergies. All these vaccine adjuvants are categorized and analyzed based on adjuvant types, pathogens used, and vaccine types. As a use case study of vaccine adjuvants in infectious disease vaccines, the adjuvants used in Brucella vaccines are specifically analyzed. A user-friendly web query and visualization interface is developed for interactive vaccine adjuvant search. To support data exchange, the information of vaccine adjuvants is stored in the Vaccine Ontology (VO) in the Web Ontology Language (OWL) format.

Vaccine process technology.

Science.gov (United States)

Josefsberg, Jessica O; Buckland, Barry

2012-06-01

The evolution of vaccines (e.g., live attenuated, recombinant) and vaccine production methods (e.g., in ovo, cell culture) are intimately tied to each other. As vaccine technology has advanced, the methods to produce the vaccine have advanced and new vaccine opportunities have been created. These technologies will continue to evolve as we strive for safer and more immunogenic vaccines and as our understanding of biology improves. The evolution of vaccine process technology has occurred in parallel to the remarkable growth in the development of therapeutic proteins as products; therefore, recent vaccine innovations can leverage the progress made in the broader biotechnology industry. Numerous important legacy vaccines are still in use today despite their traditional manufacturing processes, with further development focusing on improving stability (e.g., novel excipients) and updating formulation (e.g., combination vaccines) and delivery methods (e.g., skin patches). Modern vaccine development is currently exploiting a wide array of novel technologies to create safer and more efficacious vaccines including: viral vectors produced in animal cells, virus-like particles produced in yeast or insect cells, polysaccharide conjugation to carrier proteins, DNA plasmids produced in E. coli, and therapeutic cancer vaccines created by in vitro activation of patient leukocytes. Purification advances (e.g., membrane adsorption, precipitation) are increasing efficiency, while innovative analytical methods (e.g., microsphere-based multiplex assays, RNA microarrays) are improving process understanding. Novel adjuvants such as monophosphoryl lipid A, which acts on antigen presenting cell toll-like receptors, are expanding the previously conservative list of widely accepted vaccine adjuvants. As in other areas of biotechnology, process characterization by sophisticated analysis is critical not only to improve yields, but also to determine the final product quality. From a regulatory

Development of Streptococcus agalactiae vaccines for tilapia.

Science.gov (United States)

Liu, Guangjin; Zhu, Jielian; Chen, Kangming; Gao, Tingting; Yao, Huochun; Liu, Yongjie; Zhang, Wei; Lu, Chengping

2016-12-21

Vaccination is a widely accepted and effective method to prevent most pathogenic diseases in aquaculture. Various species of tilapia, especially Nile tilapia Oreochromis niloticus, are farmed worldwide because of their high consumer demand. Recently, the tilapia-breeding industry has been hampered by outbreaks of Streptococcus agalactiae infection, which cause high mortality and huge economic losses. Many researchers have attempted to develop effective S. agalactiae vaccines for tilapia. This review provides a summary of the different kinds of S. agalactiae vaccines for tilapia that have been developed recently. Among the various vaccine types, inactivated S. agalactiae vaccines showed superior protection efficiency when compared with live attenuated, recombinant and DNA vaccines. With respect to vaccination method, injecting the vaccine into tilapia provided the most effective immunoprotection. Freund's incomplete adjuvant appeared to be suitable for tilapia vaccines. Other factors, such as immunization duration and number, fish size and challenge dose, also influenced the vaccine efficacy.

Vaccines against enteric infections for the developing world

Science.gov (United States)

Czerkinsky, Cecil; Holmgren, Jan

2015-01-01

Since the first licensure of the Sabin oral polio vaccine more than 50 years ago, only eight enteric vaccines have been licensed for four disease indications, and all are given orally. While mucosal vaccines offer programmatically attractive tools for facilitating vaccine deployment, their development remains hampered by several factors: —limited knowledge regarding the properties of the gut immune system during early life;—lack of mucosal adjuvants, limiting mucosal vaccine development to live-attenuated or killed whole virus and bacterial vaccines;—lack of correlates/surrogates of mucosal immune protection; and—limited knowledge of the factors contributing to oral vaccine underperformance in children from developing countries.There are now reasons to believe that the development of safe and effective mucosal adjuvants and of programmatically sound intervention strategies could enhance the efficacy of current and next-generation enteric vaccines, especially in lesser developed countries which are often co-endemic for enteric infections and malnutrition. These vaccines must be safe and affordable for the world's poorest, confer long-term protection and herd immunity, and must be able to contain epidemics. PMID:25964464

Financing children's vaccines.

Science.gov (United States)

Nelson, E Anthony S; Sack, David; Wolfson, Lara; Walker, Damian G; Seng, Lim Fong; Steele, Duncan

2009-11-20

A 2006 Commonwealth Association of Paediatric Gastroenterology and Nutrition workshop on financing children's vaccines highlighted the potential for vaccines to control diarrhoea and other diseases as well as spur economic development through better health. Clear communication of vaccination value to decision-makers is required, together with sustainable funding mechanisms. GAVI and partners have made great progress providing funding for vaccines for children in the poorest countries but other solutions may be required to achieve the same gains in middle- and high-income countries. World Health Organization has a wealth of freely available country-level data on immunisation that academics and advocates can use to communicate the economic and health benefits of vaccines to decision-makers.

Microneedle patches for vaccination in developing countries.

Science.gov (United States)

Arya, Jaya; Prausnitz, Mark R

2016-10-28

Millions of people die of infectious diseases each year, mostly in developing countries, which could largely be prevented by the use of vaccines. While immunization rates have risen since the introduction of the Expanded Program on Immunization (EPI), there remain major challenges to more effective vaccination in developing countries. As a possible solution, microneedle patches containing an array of micron-sized needles on an adhesive backing have been developed to be used for vaccine delivery to the skin. These microneedle patches can be easily and painlessly applied by pressing against the skin and, in some designs, do not leave behind sharps waste. The patches are single-dose, do not require reconstitution, are easy to administer, have reduced size to simplify storage, transportation and waste disposal, and offer the possibility of improved vaccine immunogenicity, dose sparing and thermostability. This review summarizes vaccination challenges in developing countries and discusses advantages that microneedle patches offer for vaccination to address these challenges. We conclude that microneedle patches offer a powerful new technology that can enable more effective vaccination in developing countries. Copyright © 2015. Published by Elsevier B.V.

Cancer vaccines: the challenge of developing an ideal tumor killing system.

Science.gov (United States)

Mocellin, Simone

2005-09-01

Despite the evidence that the immune system plays a significant role in controlling tumor growth in natural conditions and in response to therapeutic vaccination, cancer cells can survive their attack as the disease progresses and no vaccination regimen should be currently proposed to patients outside experimental clinical trials. Clinical results show that the immune system can be actively polarized against malignant cells by means of a variety of vaccination strategies, and that in some cases this is associated with tumor regression. This implies that under some unique circumstances, the naturally "dormant" immune effectors can actually be put at work and used as endogenous weapons against malignant cells. Consequently, the main challenge of tumor immunologists appears to lie on the ability of reproducing those conditions in a larger set of patients. The complexity of the immune network and the still enigmatic host-tumor interactions make these tasks at the same time challenging and fascinating. Recent tumor immunology findings are giving new impetus to the development of more effective vaccination strategies and might revolutionize the way of designing the next generation of cancer vaccines. In the near future, the implementation of these insights in the clinical setting and the completion/conduction of comparative randomized phase III trials will allow oncologists to define the actual role of cancer vaccines in the fight against malignancy.

HIV vaccines: new frontiers in vaccine development.

Science.gov (United States)

Duerr, Ann; Wasserheit, Judith N; Corey, Lawrence

2006-08-15

A human immunodeficiency virus (HIV) vaccine is the most promising and feasible strategy to prevent the events during acute infection that simultaneously set the course of the epidemic in the community and the course of the disease for the individual. Because safety concerns limit the use of live, attenuated HIV and inactivated HIV, a variety of alternate approaches is being investigated. Traditional antibody-mediated approaches using recombinant HIV envelope proteins have shown no efficacy in 2 phase III trials. Current HIV vaccine trials are focusing primarily on cytotoxic T lymphocyte-mediated products that use viral vectors, either alone or as boosts to DNA plasmids that contain viral genes. The most immunogenic of these products appear to be the recombinant adenovirus vector vaccines, 2 of which are now in advanced clinical development.

Conjugate Meningococcal Vaccines Development: GSK Biologicals Experience

Directory of Open Access Journals (Sweden)

Jacqueline M. Miller

2011-01-01

Full Text Available Meningococcal diseases are serious threats to global health, and new vaccines specifically tailored to meet the age-related needs of various geographical areas are required. This paper focuses on the meningococcal conjugate vaccines developed by GSK Biologicals. Two combined conjugate vaccines were developed to help protect infants and young children in countries where the incidence of meningococcal serogroup C or serogroup C and Y disease is important: Hib-MenC-TT vaccine, which offers protection against Haemophilus influenzae type b and Neisseria meningitidis serogroup C diseases, is approved in several countries; and Hib-MenCY-TT vaccine, which adds N. meningitidis serogroup Y antigen, is currently in the final stages of development. Additionally, a tetravalent conjugate vaccine (MenACWY-TT designed to help protect against four meningococcal serogroups is presently being evaluated for global use in all age groups. All of these vaccines were shown to be highly immunogenic and to have clinically acceptable safety profiles.

Conjugate Meningococcal Vaccines Development: GSK Biologicals Experience

Science.gov (United States)

Miller, Jacqueline M.; Mesaros, Narcisa; Van Der Wielen, Marie; Baine, Yaela

2011-01-01

Meningococcal diseases are serious threats to global health, and new vaccines specifically tailored to meet the age-related needs of various geographical areas are required. This paper focuses on the meningococcal conjugate vaccines developed by GSK Biologicals. Two combined conjugate vaccines were developed to help protect infants and young children in countries where the incidence of meningococcal serogroup C or serogroup C and Y disease is important: Hib-MenC-TT vaccine, which offers protection against Haemophilus influenzae type b and Neisseria meningitidis serogroup C diseases, is approved in several countries; and Hib-MenCY-TT vaccine, which adds N. meningitidis serogroup Y antigen, is currently in the final stages of development. Additionally, a tetravalent conjugate vaccine (MenACWY-TT) designed to help protect against four meningococcal serogroups is presently being evaluated for global use in all age groups. All of these vaccines were shown to be highly immunogenic and to have clinically acceptable safety profiles. PMID:21991444

Development of Mycoplasma hyopneumoniae Recombinant Vaccines.

Science.gov (United States)

Marchioro, Silvana Beutinger; Simionatto, Simone; Dellagostin, Odir

2016-01-01

Mycoplasma hyopneumoniae is the etiological agent of swine enzootic pneumonia (EP), a disease that affects swine production worldwide. Vaccination is the most cost-effective strategy for the control and prevention of the disease. Research using genome-based approach has the potential to elucidate the biology and pathogenesis of M. hyopneumoniae and contribute to the development of more effective vaccines. Here, we describe the protocol for developing M. hyopneumoniae recombinant vaccines using reverse vaccinology approaches.

Vaccines against enteric infections for the developing world.

Science.gov (United States)

Czerkinsky, Cecil; Holmgren, Jan

2015-06-19

Since the first licensure of the Sabin oral polio vaccine more than 50 years ago, only eight enteric vaccines have been licensed for four disease indications, and all are given orally. While mucosal vaccines offer programmatically attractive tools for facilitating vaccine deployment, their development remains hampered by several factors: -limited knowledge regarding the properties of the gut immune system during early life; -lack of mucosal adjuvants, limiting mucosal vaccine development to live-attenuated or killed whole virus and bacterial vaccines; -lack of correlates/surrogates of mucosal immune protection; and -limited knowledge of the factors contributing to oral vaccine underperformance in children from developing countries. There are now reasons to believe that the development of safe and effective mucosal adjuvants and of programmatically sound intervention strategies could enhance the efficacy of current and next-generation enteric vaccines, especially in lesser developed countries which are often co-endemic for enteric infections and malnutrition. These vaccines must be safe and affordable for the world's poorest, confer long-term protection and herd immunity, and must be able to contain epidemics. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

WHO policy development processes for a new vaccine: case study of malaria vaccines

Directory of Open Access Journals (Sweden)

Cheyne James

2010-06-01

Full Text Available Abstract Background Recommendations from the World Health Organization (WHO are crucial to inform developing country decisions to use, or not, a new intervention. This article analysed the WHO policy development process to predict its course for a malaria vaccine. Methods The decision-making processes for one malaria intervention and four vaccines were classified through (1 consultations with staff and expert advisors to WHO's Global Malaria Programme (GMP and Immunization, Vaccines and Biologicals Department (IVB; (2 analysis of the procedures and recommendations of the major policy-making bodies of these groups; (3 interviews with staff of partnerships working toward new vaccine availability; and (4 review and analyses of evidence informing key policy decisions. Case description WHO policy formulation related to use of intermittent preventive treatment in infancy (IPTi and the following vaccine interventions: Haemophilus influenzae type b conjugate vaccine (Hib, pneumococcal conjugate vaccine (PCV, rotavirus vaccine (RV, and human papillomavirus vaccine (HPV, five interventions which had relatively recently been through systematic WHO policy development processes as currently constituted, was analysed. Required information was categorized in three areas defined by a recent WHO publication on development of guidelines: safety and efficacy in relevant populations, implications for costs and population health, and localization of data to specific epidemiological situations. Discussion and evaluation Data needs for a malaria vaccine include safety; the demonstration of efficacy in a range of epidemiological settings in the context of other malaria prevention interventions; and information on potential rebound in which disease increases subsequent to the intervention. In addition, a malaria vaccine would require attention to additional factors, such as costs and cost-effectiveness, supply and demand, impact of use on other interventions, and

Leishmaniasis vaccine candidates for development: a global overview.

Science.gov (United States)

Khamesipour, Ali; Rafati, Sima; Davoudi, Noushin; Maboudi, Fereidoun; Modabber, Farrokh

2006-03-01

A vaccine against different forms of leishmaniasis should be feasible considering the wealth of information on genetics and biology of the parasite, clinical and experimental immunology of leishmaniasis, and the availability of vaccines that can protect experimental animals against challenge with different Leishmania species. However, there is no vaccine against any form of leishmaniasis for general human use. One major factor is the lack of a conceived market for human leishmaniasis vaccines. Hence pharmaceutical industries involved in vaccine development are not interested in investing millions of dollars and a decade that is required for developing a new vaccine. Besides, leishmaniasis is a local/regional problem and not a global one. According to the estimates of the World Health Organization, 90 per cent of visceral leishmaniasis occurs in five countries (Bangladesh, Brazil, India, Nepal and Sudan). Those in need are amongst the poorest people in these countries. It should therefore be the objectives of these countries to develop a vaccine. Fortunately, both Brazil and India have designated the control of visceral leishmaniasis as a top priority for their respective Ministries of Health. The purpose of this review is to present only the vaccines in use and those in development for use in dogs or humans. This is not an exhaustive review of vaccine discovery or the principles of clinical immunology underlying vaccine development.

DENGUE VACCINE, CHALLENGES, DEVELOPMENT AND STRATEGIES

Directory of Open Access Journals (Sweden)

Dewi Marbawati

2014-08-01

Full Text Available ABSTRAKPenyakit demam Dengue endemik di lebih dari 100 negara di dunia. Obat anti virus Dengue efektif belum ditemukan danpengendalian vektor dinilai kurang efektif, sehingga diperlukan upaya pencegahan dengan vaksinasi. Vaksin Dengue yangideal adalah murah, mencakup 4 serotipe, efektif dalam memberikan kekebalan, cukup diberikan sekali seumur hidup, aman,memberi kekebalan jangka panjang, stabil dalam penyimpanan dan stabil secara genetis (tidak bermutasi. Beberapakandidat vaksin yang telah dan sedang dikembangkan oleh para peneliti di seluruh dunia adalah tetravalent live attenuatedvaccine, vaksin Chimera (ChimeriVax, vaksin subunit dan vaksin DNA. Vaksin Dengue dipandang sebagai pendekatan yangefektif dan berkesinambungan dalam mengendalikan penyakit Dengue. Tahun 2003 telah terbentuk Pediatric DengueVaccine Initiative (PDVI, yaitu sebuah konsorsium internasional yang bergerak dalam advokasi untuk meyakinkanmasyarakat internasional akan penting dan mendesaknya vaksin Dengue. Konsorsium vaksin Dengue Indonesia saat iniberupaya mengembangkan vaksin Dengue dengan menggunakan strain virus lokal.Kata kunci: Dengue, virus, vaksinABSTRACTDengue fever is endemic in more than 100 countries in the world. The effective dengue antiviral drug has not been found yet,and vector control is considered less effective. Prevention program by vaccination is needed. An ideal dengue vaccine shouldbe inexpensive, covering four serotypes (tetravalent, effective in providing immunity, given once a lifetime, safe, stable instorage and genetically. Several vaccine candidates have been and are being developed included attenuated tetravalentvaccine, ChimeriVax, sub- unit vaccines and DNA vaccines. Dengue vaccine is seen as an effective and sustainable approachto controll Dengue infection. In 2003, Pediatric Dengue Vaccine Initiative (PDVI has been formed as an internationalconsortium involved in advocacy to convince the international community about the essence and urgency

Strategies for Cancer Vaccine Development

Directory of Open Access Journals (Sweden)

Matteo Vergati

2010-01-01

Full Text Available Treating cancer with vaccines has been a challenging field of investigation since the 1950s. Over the years, the lack of effective active immunotherapies has led to the development of numerous novel strategies. However, the use of therapeutic cancer vaccines may be on the verge of becoming an effective modality. Recent phase II/III clinical trials have achieved hopeful results in terms of overall survival. Yet despite these encouraging successes, in general, very little is known about the basic immunological mechanisms involved in vaccine immunotherapy. Gaining a better understanding of the mechanisms that govern the specific immune responses (i.e., cytotoxic T lymphocytes, CD4 T helper cells, T regulatory cells, cells of innate immunity, tumor escape mechanisms elicited by each of the various vaccine platforms should be a concern of cancer vaccine clinical trials, along with clinical benefits. This review focuses on current strategies employed by recent clinical trials of therapeutic cancer vaccines and analyzes them both clinically and immunologically.

Status of vaccine research and development of vaccines for leishmaniasis.

Science.gov (United States)

Gillespie, Portia M; Beaumier, Coreen M; Strych, Ulrich; Hayward, Tara; Hotez, Peter J; Bottazzi, Maria Elena

2016-06-03

A number of leishmaniasis vaccine candidates are at various stages of pre-clinical and clinical development. Leishmaniasis is a vector-borne neglected tropical disease (NTD) caused by a protozoan parasite of the genus Leishmania and transmitted to humans by the bite of a sand fly. Visceral leishmaniasis (VL, kala-azar) is a high mortality NTD found mostly in South Asia and East Africa, while cutaneous leishmaniasis (CL) is a disfiguring NTD highly endemic in the Middle East, Central Asia, North Africa, and the Americas. Estimates attribute 50,000 annual deaths and 3.3 million disability-adjusted life years to leishmaniasis. There are only a few approved drug treatments, no prophylactic drug and no vaccine. Ideally, an effective vaccine against leishmaniasis will elicit long-lasting immunity and protect broadly against VL and CL. Vaccines such as Leish-F1, F2 and F3, developed at IDRI and designed based on selected Leishmania antigen epitopes, have been in clinical trials. Other groups, including the Sabin Vaccine Institute in collaboration with the National Institutes of Health are investigating recombinant Leishmania antigens in combination with selected sand fly salivary gland antigens in order to augment host immunity. To date, both VL and CL vaccines have been shown to be cost-effective in economic modeling studies. Copyright © 2016 World Health Organization. Published by Elsevier Ltd.. All rights reserved.

Development of Novel Vaccines against Enterovirus-71

Science.gov (United States)

Yee, Pinn Tsin Isabel; Poh, Chit Laa

2015-01-01

The hand, foot and mouth disease is caused by a group of Enteroviruses such as Enterovirus 71 (EV-A71) and Coxsackievirus CV-A5, CV-A8, and CV-A16. Mild symptoms of EV-A71 infection in children range from high fever, vomiting, rashes and ulcers in mouth but can produce more severe symptoms such as brainstem and cerebellar encephalitis, leading up to cardiopulmonary failure and death. The lack of vaccines and antiviral drugs against EV-A71 highlights the urgency of developing preventive and treatment agents against EV-A71 to prevent further fatalities. Research groups have developed experimental inactivated vaccines, recombinant Viral Protein 1 (VP1) vaccine and virus-like particles (VLPs). The inactivated EV-A71 vaccine is considered the safest viral vaccine, as there will be no reversion to the infectious wild type strain. The recombinant VP1 vaccine is a cost-effective immunogen, while VLPs contain an arrangement of epitopes that can elicit neutralizing antibodies against the virus. As each type of vaccine has its advantages and disadvantages, increased studies are required in the development of such vaccines, whereby high efficacy, long-lasting immunity, minimal risk to those vaccinated, safe and easy production, low cost, dispensing the need for refrigeration and convenient delivery are the major goals in their design. PMID:26729152

Vaccine prophylaxis: achievements, problems, perspectives of development

Directory of Open Access Journals (Sweden)

Mavrutenkov V.V.

2016-09-01

Full Text Available The article presents medical and social aspects of immune prophylaxis of infectious diseases; the history of vaccines and vaccination is presented, as well as perspectives of development of vaccine prophylaxis.

The future of HIV vaccine research and the role of the Global HIV Vaccine Enterprise.

Science.gov (United States)

Voronin, Yegor; Manrique, Amapola; Bernstein, Alan

2010-09-01

This review covers the role of the Global HIV Vaccine Enterprise (the Enterprise), an alliance of independent organizations committed to development of a safe and effective HIV vaccine. It discusses the history, impact on the field, and future directions and initiatives of the alliance in the context of recent progress in HIV vaccine research and development. Significant progress has been made in the field since the release of the 2005 Scientific Strategic Plan (the Plan) of the Enterprise. Over the last year, the Enterprise embarked on an impact assessment of the 2005 Plan and the development of the 2010 Plan. Enterprise Working Groups identified key priorities in the field, several of which are discussed in this review, including changing the nature, purpose and process of clinical trials, increasing and facilitating data sharing, and optimizing existing and mobilizing new resources. This time is an important moment in HIV vaccine research. New clinical trial and laboratory results have created new opportunities to advance the search for an HIV vaccine and reinvigorated the field. The Enterprise will publish its 2010 Plan this year, providing a framework for setting new priorities and directions and encouraging new and existing partners to embark on a shared scientific agenda.

Zika Vaccine Development: Flavivirus Foils

Science.gov (United States)

2016-09-01

Martins, Bavari, Zika Vaccine Development 1 Zika Vaccine Development: Flavivirus Foils Martins KAO, Bavari S. The current Zika virus...States government. The rapid response to Zika is perhaps the first of its kind, and it undoubtedly has been made possible by the lessons learned from...the response to the 2014 Ebola virus outbreak in West Africa. However, Zika virus is not Ebola virus. As of February 2016 there were only 296

Development and trial of vaccines against Brucella.

Science.gov (United States)

Lalsiamthara, Jonathan; Lee, John Hwa

2017-08-31

The search for ideal brucellosis vaccines remains active today. Currently, no licensed human or canine anti-brucellosis vaccines are available. In bovines, the most successful vaccine (S19) is only used in calves, as adult vaccination results in orchitis in male, prolonged infection, and possible abortion complications in pregnant female cattle. Another widely deployed vaccine (RB51) has a low protective efficacy. An ideal vaccine should exhibit a safe profile as well as enhance protective efficacy. However, currently available vaccines exhibit one or more major drawbacks. Smooth live attenuated vaccines suffer shortcomings such as residual virulence and serodiagnostic interference. Inactivated vaccines, in general, confer relatively low levels of protection. Recent developments to improve brucellosis vaccines include generation of knockout mutants by targeting genes involved in metabolism, virulence, and the lipopolysaccharide synthesis pathway, as well as generation of DNA vaccines, mucosal vaccines, and live vectored vaccines, have all produced varying degrees of success. Herein, we briefly review the bacteriology, pathogenesis, immunological implications, candidate vaccines, vaccinations, and models related to Brucella .

Evolution of Live-Attenuated HIV Vaccines

NARCIS (Netherlands)

Berkhout, Ben

2011-01-01

Despite intensive research since the viral pathogen was discovered some 25 years ago, not much progress has been reported on the development of a safe vaccine that protects against human immunodeficiency virus type 1. A vaccine approach that has been abandoned because its safety cannot be guaranteed

Recombinant vaccines and the development of new vaccine strategies

Energy Technology Data Exchange (ETDEWEB)

Nascimento, I.P.; Leite, L.C.C. [Centro de Biotecnologia, Instituto Butantan, São Paulo, SP (Brazil)

2012-09-07

Vaccines were initially developed on an empirical basis, relying mostly on attenuation or inactivation of pathogens. Advances in immunology, molecular biology, biochemistry, genomics, and proteomics have added new perspectives to the vaccinology field. The use of recombinant proteins allows the targeting of immune responses focused against few protective antigens. There are a variety of expression systems with different advantages, allowing the production of large quantities of proteins depending on the required characteristics. Live recombinant bacteria or viral vectors effectively stimulate the immune system as in natural infections and have intrinsic adjuvant properties. DNA vaccines, which consist of non-replicating plasmids, can induce strong long-term cellular immune responses. Prime-boost strategies combine different antigen delivery systems to broaden the immune response. In general, all of these strategies have shown advantages and disadvantages, and their use will depend on the knowledge of the mechanisms of infection of the target pathogen and of the immune response required for protection. In this review, we discuss some of the major breakthroughs that have been achieved using recombinant vaccine technologies, as well as new approaches and strategies for vaccine development, including potential shortcomings and risks.

Recombinant vaccines and the development of new vaccine strategies

Directory of Open Access Journals (Sweden)

I.P. Nascimento

2012-12-01

Full Text Available Vaccines were initially developed on an empirical basis, relying mostly on attenuation or inactivation of pathogens. Advances in immunology, molecular biology, biochemistry, genomics, and proteomics have added new perspectives to the vaccinology field. The use of recombinant proteins allows the targeting of immune responses focused against few protective antigens. There are a variety of expression systems with different advantages, allowing the production of large quantities of proteins depending on the required characteristics. Live recombinant bacteria or viral vectors effectively stimulate the immune system as in natural infections and have intrinsic adjuvant properties. DNA vaccines, which consist of non-replicating plasmids, can induce strong long-term cellular immune responses. Prime-boost strategies combine different antigen delivery systems to broaden the immune response. In general, all of these strategies have shown advantages and disadvantages, and their use will depend on the knowledge of the mechanisms of infection of the target pathogen and of the immune response required for protection. In this review, we discuss some of the major breakthroughs that have been achieved using recombinant vaccine technologies, as well as new approaches and strategies for vaccine development, including potential shortcomings and risks.

Recombinant vaccines and the development of new vaccine strategies

International Nuclear Information System (INIS)

Nascimento, I.P.; Leite, L.C.C.

2012-01-01

Vaccines were initially developed on an empirical basis, relying mostly on attenuation or inactivation of pathogens. Advances in immunology, molecular biology, biochemistry, genomics, and proteomics have added new perspectives to the vaccinology field. The use of recombinant proteins allows the targeting of immune responses focused against few protective antigens. There are a variety of expression systems with different advantages, allowing the production of large quantities of proteins depending on the required characteristics. Live recombinant bacteria or viral vectors effectively stimulate the immune system as in natural infections and have intrinsic adjuvant properties. DNA vaccines, which consist of non-replicating plasmids, can induce strong long-term cellular immune responses. Prime-boost strategies combine different antigen delivery systems to broaden the immune response. In general, all of these strategies have shown advantages and disadvantages, and their use will depend on the knowledge of the mechanisms of infection of the target pathogen and of the immune response required for protection. In this review, we discuss some of the major breakthroughs that have been achieved using recombinant vaccine technologies, as well as new approaches and strategies for vaccine development, including potential shortcomings and risks

[HPV Vaccination Program - The History and Recent Progress].

Science.gov (United States)

Yoshikawa, Hiroyuki

2017-09-01

Four years have passed since HPV vaccination "crisis" occurred in June 2013. In Japan,a publicly funded HPV vaccination program for adolescent females aged 12-16 years began in December 2010. However,the Japanese government withdrew its recommendation for HPV vaccination in June, 2013 because news reports on potential adverse effects of HPV vaccines without any medical evidence appeared repeatedly. The vaccination coverage among adolescent females decreased quickly from around 70%in females born between 1994 and 1999 to only 1%in females born since 2001 over the country. The suspension of recommendation for vaccination has continued to the present,though there is no scientific or epidemiologic evidence to demonstrate the causal linkage between post-vaccination symptoms and the HPV vaccines. Very recently,an ecological investigation reported that similar symptoms also occur in unvaccinated adolescents in Japan. Medical organizations in Japan are also calling for a resumption of the HPV vaccination program. Now,the resumption of the recommendation needs a political judgment.

Development of a Vaccine against Escherichia coli Urinary Tract Infections

Directory of Open Access Journals (Sweden)

Harry L. T. Mobley

2015-12-01

Full Text Available Urinary tract infection (UTI is the second most common infection in humans after those involving the respiratory tract. This results not only in huge annual economic costs, but in decreased workforce productivity and high patient morbidity. Most infections are caused by uropathogenic Escherichia coli (UPEC. Antibiotic treatment is generally effective for eradication of the infecting strain; however, documentation of increasing antibiotic resistance, allergic reaction to certain pharmaceuticals, alteration of normal gut flora, and failure to prevent recurrent infections represent significant barriers to treatment. As a result, approaches to prevent UTI such as vaccination represent a gap that must be addressed. Our laboratory has made progress toward development of a preventive vaccine against UPEC. The long-term research goal is to prevent UTIs in women with recurrent UTIs. Our objective has been to identify the optimal combination of protective antigens for inclusion in an effective UTI vaccine, optimal adjuvant, optimal dose, and optimal route of delivery. We hypothesized that a multi-subunit vaccine elicits antibody that protects against experimental challenge with UPEC strains. We have systematically identified four antigens that can individually protect experimentally infected mice from colonization of the bladder and/or kidneys by UPEC when administered intranasally with cholera toxin (CT as an adjuvant. To advance the vaccine for utility in humans, we will group the individual antigens, all associated with iron acquisition (IreA, Hma, IutA, FyuA, into an effective combination to establish a multi-subunit vaccine. We demonstrated for all four vaccine antigens that antigen-specific serum IgG represents a strong correlate of protection in vaccinated mice. High antibody titers correlate with low colony forming units (CFUs of UPEC following transurethral challenge of vaccinated mice. However, the contribution of cell-mediated immunity cannot

How influenza vaccination policy may affect vaccine logistics.

Science.gov (United States)

Assi, Tina-Marie; Rookkapan, Korngamon; Rajgopal, Jayant; Sornsrivichai, Vorasith; Brown, Shawn T; Welling, Joel S; Norman, Bryan A; Connor, Diana L; Chen, Sheng-I; Slayton, Rachel B; Laosiritaworn, Yongjua; Wateska, Angela R; Wisniewski, Stephen R; Lee, Bruce Y

2012-06-22

When policymakers make decision about the target populations and timing of influenza vaccination, they may not consider the impact on the vaccine supply chains, which may in turn affect vaccine availability. Our goal is to explore the effects on the Thailand vaccine supply chain of introducing influenza vaccines and varying the target populations and immunization time-frames. We Utilized our custom-designed software HERMES (Highly Extensible Resource for Modeling Supply Chains), we developed a detailed, computational discrete-event simulation model of the Thailand's National Immunization Program (NIP) supply chain in Trang Province, Thailand. A suite of experiments simulated introducing influenza vaccines for different target populations and over different time-frames prior to and during the annual influenza season. Introducing influenza vaccines creates bottlenecks that reduce the availability of both influenza vaccines as well as the other NIP vaccines, with provincial to district transport capacity being the primary constraint. Even covering only 25% of the Advisory Committee on Immunization Practice-recommended population while administering the vaccine over six months hinders overall vaccine availability so that only 62% of arriving patients can receive vaccines. Increasing the target population from 25% to 100% progressively worsens these bottlenecks, while increasing influenza vaccination time-frame from 1 to 6 months decreases these bottlenecks. Since the choice of target populations for influenza vaccination and the time-frame to deliver this vaccine can substantially affect the flow of all vaccines, policy-makers may want to consider supply chain effects when choosing target populations for a vaccine. Copyright © 2012 Elsevier Ltd. All rights reserved.

Vaccine procurement and self-sufficiency in developing countries.

Science.gov (United States)

Woodle, D

2000-06-01

This paper discusses the movement toward self-sufficiency in vaccine supply in developing countries (and countries in transition to new economic and political systems) and explains special supply concerns about vaccine as a product class. It traces some history of donor support and programmes aimed at self-financing, then continues with a discussion about self-sufficiency in terms of institutional capacity building. A number of deficiencies commonly found in vaccine procurement and supply in low- and middle-income countries are characterized, and institutional strengthening with procurement technical assistance is described. The paper also provides information about a vaccine procurement manual being developed by the United States Agency for International Development (USAID) and the World Health Organization (WHO) for use in this environment. Two brief case studies are included to illustrate the spectrum of existing capabilities and different approaches to technical assistance aimed at developing or improving vaccine procurement capability. In conclusion, the paper discusses the special nature of vaccine and issues surrounding potential integration and decentralization of vaccine supply systems as part of health sector reform.

Recombinant and epitope-based vaccines on the road to the market and implications for vaccine design and production.

Science.gov (United States)

Oyarzún, Patricio; Kobe, Bostjan

2016-03-03

Novel vaccination approaches based on rational design of B- and T-cell epitopes - epitope-based vaccines - are making progress in the clinical trial pipeline. The epitope-focused recombinant protein-based malaria vaccine (termed RTS,S) is a next-generation approach that successfully reached phase-III trials, and will potentially become the first commercial vaccine against a human parasitic disease. Progress made on methods such as recombinant DNA technology, advanced cell-culture techniques, immunoinformatics and rational design of immunogens are driving the development of these novel concepts. Synthetic recombinant proteins comprising both B- and T-cell epitopes can be efficiently produced through modern biotechnology and bioprocessing methods, and can enable the induction of large repertoires of immune specificities. In particular, the inclusion of appropriate CD4+ T-cell epitopes is increasingly considered a key vaccine component to elicit robust immune responses, as suggested by results coming from HIV-1 clinical trials. In silico strategies for vaccine design are under active development to address genetic variation in pathogens and several broadly protective "universal" influenza and HIV-1 vaccines are currently at different stages of clinical trials. Other methods focus on improving population coverage in target populations by rationally considering specificity and prevalence of the HLA proteins, though a proof-of-concept in humans has not been demonstrated yet. Overall, we expect immunoinformatics and bioprocessing methods to become a central part of the next-generation epitope-based vaccine development and production process.

Vaccines to combat the neglected tropical diseases

Science.gov (United States)

Bethony, Jeffrey M.; Cole, Rhea N.; Guo, Xiaoti; Kamhawi, Shaden; Lightowlers, Marshall W.; Loukas, Alex; Petri, William; Reed, Steven; Valenzuela, Jesus G.; Hotez, Peter J.

2012-01-01

Summary The neglected tropical diseases (NTDs) represent a group of parasitic and related infectious diseases such as amebiasis, Chagas disease, cysticercosis, echinococcosis, hookworm, leishmaniasis, and schistosomiasis. Together, these conditions are considered the most common infections in low- and middle-income countries, where they produce a level of global disability and human suffering equivalent to better known conditions such as human immunodeficiency virus/acquired immunodeficiency syndrome and malaria. Despite their global public health importance, progress on developing vaccines for NTD pathogens has lagged because of some key technical hurdles and the fact that these infections occur almost exclusively in the world’s poorest people living below the World Bank poverty line. In the absence of financial incentives for new products, the multinational pharmaceutical companies have not embarked on substantive research and development programs for the neglected tropical disease vaccines. Here, we review the current status of scientific and technical progress in the development of new neglected tropical disease vaccines, highlighting the successes that have been achieved (cysticercosis and echinococcosis) and identifying the challenges and opportunities for development of new vaccines for NTDs. Also highlighted are the contributions being made by non-profit product development partnerships that are working to overcome some of the economic challenges in vaccine manufacture, clinical testing, and global access. PMID:21198676

Mucosal vaccines: recent progress in understanding the natural barriers.

Science.gov (United States)

Borges, Olga; Lebre, Filipa; Bento, Dulce; Borchard, Gerrit; Junginger, Hans E

2010-02-01

It has long been known that protection against pathogens invading the organism via mucosal surfaces correlates better with the presence of specific antibodies in local secretions than with serum antibodies. The most effective way to induce mucosal immunity is to administer antigens directly to the mucosal surface. The development of vaccines for mucosal application requires antigen delivery systems and immunopotentiators that efficiently facilitate the presentation of the antigen to the mucosal immune system. This review provides an overview of the events within mucosal tissues that lead to protective mucosal immune responses. The understanding of those biological mechanisms, together with knowledge of the technology of vaccines and adjuvants, provides guidance on important technical aspects of mucosal vaccine design. Not being exhaustive, this review also provides information related to modern adjuvants, including polymeric delivery systems and immunopotentiators.

HIV vaccine development: would more (public) money bring quicker results?

Science.gov (United States)

Winsbury, R

1999-01-01

Globally, $200-250 million/year are devoted to HIV vaccine research. Most of those funds pay for basic research rather than product development. Moreover, most of the funds are aimed at the HIV strain commonly found in the US and Europe, and not at the strains common to Africa and other developing countries. While US President Bill Clinton set in 1997 a 10-year target for the development of an HIV vaccine, that target date is looking increasingly unlikely. International vaccine and pharmaceutical companies typically drive vaccine research and development. However, concern over the ultimate profitability of developing and marketing an HIV vaccine, and the fear of major litigation should an eventual vaccine go awry have caused such firms to shy away from investing large amounts of money into HIV vaccine development. These companies somehow have to be attracted back into the field. A World Bank special task force is slated to present its report by mid-1999 on possible funding mechanisms to promote HIV vaccine development. It remains to be resolved whether public funds could and should be used, perhaps through a pooled international vaccine development fund. 2 new International AIDS Vaccine Initiative projects are described.

Successes and failures in human tuberculosis vaccine development.

Science.gov (United States)

Zenteno-Cuevas, Roberto

2017-12-01

Tuberculosis (TB) is an infectious disease caused mainly by Mycobacterium tuberculosis. In 2016, the WHO estimated 10.5 million new cases and 1.8 million deaths, making this disease the leading cause of death by an infectious agent. The current and projected TB situation necessitates the development of new vaccines with improved attributes compared to the traditional BCG method. Areas covered: In this review, the authors describe the most promising candidate vaccines against TB and discuss additional key elements in vaccine development, such as animal models, new adjuvants and immunization routes and new strategies for the identification of candidate vaccines. Expert opinion: At present, around 13 candidate vaccines for TB are in the clinical phase of evaluation; however, there is still no substitute for the BCG vaccine. One major impediment to developing an effective vaccine is our lack of understanding of several of the mechanisms associated with infection and the immune response against TB. However, the recent implementation of an entirely new set of technological advances will facilitate the proposal of new candidates. Finally, development of a new vaccine will require a major coordination of effort in order to achieve its effective administration to the people most in need of it.

New vaccines for neglected parasitic diseases and dengue.

Science.gov (United States)

Beaumier, Coreen M; Gillespie, Portia M; Hotez, Peter J; Bottazzi, Maria Elena

2013-09-01

Neglected tropical diseases (NTDs) are a significant source of morbidity and socioeconomic burden among the world's poor. Virtually all of the 2.4 billion people who live on less than $2 per d, more than a third of the world's population, are at risk for these debilitating NTDs. Although chemotherapeutic measures exist for many of these pathogens, they are not sustainable countermeasures on their own because of rates of reinfection, risk of drug resistance, and inconsistent maintenance of drug treatment programs. Preventative and therapeutic NTD vaccines are needed as long-term solutions. Because there is no market in the for-profit sector of vaccine development for these pathogens, much of the effort to develop vaccines is driven by nonprofit entities, mostly through product development partnerships. This review describes the progress of vaccines under development for many of the NTDs, with a specific focus on those about to enter or that are currently in human clinical trials. Specifically, we report on the progress on dengue, hookworm, leishmaniasis, schistosomiasis, Chagas disease, and onchocerciasis vaccines. These products will be some of the first with specific objectives to aid the world's poorest populations. Copyright © 2013 Mosby, Inc. All rights reserved.

Impact of an HPV6/11/16/18 L1 virus-like particle vaccine on progression to cervical intraepithelial neoplasia in seropositive women with HPV16/18 infection

DEFF Research Database (Denmark)

Haupt, Richard M; Wheeler, Cosette M; Brown, Darron R

2011-01-01

The impact of a human papillomavirus (HPV) vaccine on development of cervical intraepithelial neoplasia grade 2-3 or adenocarcinoma in situ (CIN2-3/AIS) in women with ongoing HPV16 or 18 infections prevaccination is reported. Seventeen thousand six-hundred and twenty-two women aged 16-26 were.......9). These data suggest HPV vaccination neither reduces nor enhances progression to HPV16/18-related high grade cervical lesions, and cervical cytology screening and corresponding management should continue as per local recommendations. Ultimately, population-based surveillance of vaccinated individuals beyond...

Genome-derived vaccines.

Science.gov (United States)

De Groot, Anne S; Rappuoli, Rino

2004-02-01

Vaccine research entered a new era when the complete genome of a pathogenic bacterium was published in 1995. Since then, more than 97 bacterial pathogens have been sequenced and at least 110 additional projects are now in progress. Genome sequencing has also dramatically accelerated: high-throughput facilities can draft the sequence of an entire microbe (two to four megabases) in 1 to 2 days. Vaccine developers are using microarrays, immunoinformatics, proteomics and high-throughput immunology assays to reduce the truly unmanageable volume of information available in genome databases to a manageable size. Vaccines composed by novel antigens discovered from genome mining are already in clinical trials. Within 5 years we can expect to see a novel class of vaccines composed by genome-predicted, assembled and engineered T- and Bcell epitopes. This article addresses the convergence of three forces--microbial genome sequencing, computational immunology and new vaccine technologies--that are shifting genome mining for vaccines onto the forefront of immunology research.

Vaccines for preventing infection with Pseudomonas aeruginosa in cystic fibrosis

DEFF Research Database (Denmark)

Johansen, Helle Krogh; Gøtzsche, Peter C

2013-01-01

Chronic pulmonary infection in cystic fibrosis results in progressive lung damage. Once colonisation of the lungs with Pseudomonas aeruginosa occurs, it is almost impossible to eradicate. Vaccines, aimed at reducing infection with Pseudomonas aeruginosa, have been developed.......Chronic pulmonary infection in cystic fibrosis results in progressive lung damage. Once colonisation of the lungs with Pseudomonas aeruginosa occurs, it is almost impossible to eradicate. Vaccines, aimed at reducing infection with Pseudomonas aeruginosa, have been developed....

Varicella and herpes zoster vaccine development: lessons learned.

Science.gov (United States)

Warren-Gash, Charlotte; Forbes, Harriet; Breuer, Judith

2017-12-01

Before vaccination, varicella zoster virus (VZV), which is endemic worldwide, led to almost universal infection. This neurotropic virus persists lifelong by establishing latency in sensory ganglia, where its reactivation is controlled by VZV-specific T-cell immunity. Lifetime risk of VZV reactivation (zoster) is around 30%. Vaccine development was galvanised by the economic and societal burden of VZV, including debilitating zoster complications that largely affect older individuals. Areas covered: We describe the story of development, licensing and implementation of live attenuated vaccines against varicella and zoster. We consider the complex backdrop of VZV virology, pathogenesis and immune responses in the absence of suitable animal models and examine the changing epidemiology of VZV disease. We review the vaccines' efficacy, safety, effectiveness and coverage using evidence from trials, observational studies from large routine health datasets and clinical post-marketing surveillance studies and outline newer developments in subunit and inactivated vaccines. Expert commentary: Safe and effective, varicella and zoster vaccines have already made major inroads into reducing the burden of VZV disease globally. As these live vaccines have the potential to reactivate and cause clinical disease, developing alternatives that do not establish latency is an attractive prospect but will require better understanding of latency mechanisms.

Malnutrition and vaccination in developing countries

Science.gov (United States)

Prendergast, Andrew J.

2015-01-01

Malnutrition contributes to an estimated 45% of deaths among children under 5 years of age in developing countries, predominantly due to infections. Malnourished children therefore stand to benefit hugely from vaccination, but malnutrition has been described as the most common immunodeficiency globally, suggesting that they may not be able to respond effectively to vaccines. The immunology of malnutrition remains poorly characterized, but is associated with impairments in mucosal barrier integrity, and innate and adaptive immune dysfunction. Despite this, the majority of malnourished children can mount a protective immune response following vaccination, although the timing, quality and duration of responses may be impaired. This paper reviews the evidence for vaccine immunogenicity in malnourished children, discusses the importance of vaccination in prevention of malnutrition and highlights evidence gaps in our current knowledge. PMID:25964453

A history of the development of Brucella vaccines.

Science.gov (United States)

Avila-Calderón, Eric Daniel; Lopez-Merino, Ahidé; Sriranganathan, Nammalwar; Boyle, Stephen M; Contreras-Rodríguez, Araceli

2013-01-01

Brucellosis is a worldwide zoonosis affecting animal and human health. In the last several decades, much research has been performed to develop safer Brucella vaccines to control the disease mainly in animals. Till now, no effective human vaccine is available. The aim of this paper is to review and discuss the importance of methodologies used to develop Brucella vaccines in pursuing this challenge.

Virulence determinants of Moraxella catarrhalis: distribution and considerations for vaccine development.

Science.gov (United States)

Blakeway, Luke V; Tan, Aimee; Peak, Ian R A; Seib, Kate L

2017-10-01

Moraxella catarrhalis is a human-restricted opportunistic bacterial pathogen of the respiratory mucosa. It frequently colonizes the nasopharynx asymptomatically, but is also an important causative agent of otitis media (OM) in children, and plays a significant role in acute exacerbations of chronic obstructive pulmonary disease (COPD) in adults. As the current treatment options for M. catarrhalis infection in OM and exacerbations of COPD are often ineffective, the development of an efficacious vaccine is warranted. However, no vaccine candidates for M. catarrhalis have progressed to clinical trials, and information regarding the distribution of M. catarrhalis virulence factors and vaccine candidates is inconsistent in the literature. It is largely unknown if virulence is associated with particular strains or subpopulations of M. catarrhalis, or if differences in clinical manifestation can be attributed to the heterogeneous expression of specific M. catarrhalis virulence factors in the circulating population. Further investigation of the distribution of M. catarrhalis virulence factors in the context of carriage and disease is required so that vaccine development may be targeted at relevant antigens that are conserved among disease-causing strains. The challenge of determining which of the proposed M. catarrhalis virulence factors are relevant to human disease is amplified by the lack of a standardized M. catarrhalis typing system to facilitate direct comparisons of worldwide isolates. Here we summarize and evaluate proposed relationships between M. catarrhalis subpopulations and specific virulence factors in the context of colonization and disease, as well as the current methods used to infer these associations.

Vaccines, inspiring innovation in health.

Science.gov (United States)

Pagliusi, Sonia; Dennehy, Maureen; Kim, Hun

2018-05-19

This report covers the topics of pandemics, epidemics and partnerships, including regulatory convergence initiatives, new technologies and novel vaccines, discussed by leading public and private sector stakeholders at the 18th Annual General Meeting (AGM) of the Developing Countries Vaccine Manufacturers' Network (DCVMN). Contributions of Gavi and the vaccine industry from emerging countries to the growing global vaccine market, by improving the supply base from manufacturers in developing countries and contributing to 58% of doses, were highlighted. The Coalition for Epidemic Preparedness Innovations (CEPI), the International Vaccine Institute (IVI) and others reported on new strategies to ensure speedy progress in preclinical and clinical development of innovative vaccines for future MERS, Zika or other outbreak response. Priorities for vaccine stockpiling, to assure readiness during emergencies and to prevent outbreaks due to re-emerging diseases such as yellow fever, cholera and poliomyelitis, were outlined. The role of partnerships in improving global vaccine access, procurement and immunization coverage, and shared concerns were reviewed. The World Health Organization (WHO) and other international collaborating partners provided updates on the Product, Price and Procurement database, the prequalification of vaccines, the control of neglected tropical diseases, particularly the new rabies elimination initiative, and regulatory convergence proposals to accelerate vaccine registration in developing countries. Updates on supply chain innovations and novel vaccine platforms were presented. The discussions enabled members and partners to reflect on efficiency of research & development, supply chain tools and trends in packaging technologies improving delivery of existing vaccines, and allowing a deeper understanding of the current public-health objectives, industry financing, and global policies, required to ensure optimal investments, alignment and stability of

Vaccines licensed and in clinical trials for the prevention of dengue.

Science.gov (United States)

Torresi, J; Ebert, G; Pellegrini, M

2017-05-04

Dengue has become a major global public health threat with almost half of the world's population living in at-risk areas. Vaccination would likely represent an effective strategy for the management of dengue disease in endemic regions, however to date there is only one licensed preventative vaccine for dengue infection. The development of a vaccine against dengue virus (DENV) has been hampered by an incomplete understanding of protective immune responses against DENV. The most clinically advanced dengue vaccine is the chimeric yellow fever-dengue vaccine (CYD) that employs the yellow fever virus 17D strain as the replication backbone (Chimerivax-DEN; CYD-TDV). This vaccine had an overall pooled protective efficacy of 65.6% but was substantially more effective against severe dengue and dengue hemorrhagic fever. Several other vaccine approaches have been developed including live attenuated chimeric dengue vaccines (DENVax and LAV Delta 30), DEN protein subunit V180 vaccine (DEN1-80E) and DENV DNA vaccines. These vaccines have been shown to be immunogenic in animals and also safe and immunogenic in humans. However, these vaccines are yet to progress to phase III trials to determine their protective efficacy against dengue. This review will summarize the details of vaccines that have progressed to clinical trials in humans.

Progress toward development of photodynamic vaccination against infectious/malignant diseases and photodynamic mosquitocides

Science.gov (United States)

Chang, Kwang Poo; Kolli, Bala K.; Fan, Chia-Kwung; Ng, Dennis K. P.; Wong, Clarence T. T.; Manna, Laura; Corso, Raffaele; Shih, Neng-Yao; Elliott, Robert; Jiang, X. P.; Shiao, Shin-Hong; Fu, Guo-Liang

2018-02-01

Photodynamic therapy (PDT) uses photosensitizers (PS) that are excited with light to generate ROS in the presence of oxygen for treating various diseases. PS also has the potential use as photodynamic insecticides (PDI) and for light-inactivation of Leishmania for photodynamic vaccination (PDV). PDT-inactivated Leishmania are non-viable, but remain immunologically competent as whole-cell vaccines against leishmaniasis, and as a universal carrier for delivery of add-on vaccines against other infectious and malignant diseases. We have screened novel PS, including Zn- and Si-phthalocyanines (PC) for differential PDT activities against Leishmania, insect and mammalian cells in vitro to assess their PDI and PDV potential. Here, Zn-PC were conjugated with various functional groups. The conjugates were examined for uptake by cells as a prerequisite for their susceptibility to light-inactivation. PDT sensitivity was found to vary with cell types and PS used. PDI potential of several PS was demonstrated by their mosquito larvicidal PDT activities in vitro. PDT-inactivated Leishmania were stored frozen for PDV in several ongoing studies: [1] Open label trial with 20 sick dogs for immunotherapy of canine leishmaniasis after chemotherapy in Naples, Italy. Clinical follow-up for >3 years indicate that the PDV prolongs their survival; [2] PDV of murine models with a human lung cancer vaccine showed dramatic tumor suppression; [3] Open label trial of multiple PDV via compassionate access to 4 advanced cancer patients showed no clinically adverse effects. Two subjects remain alive. Genetic modifications of Leishmania are underway to further enhance their safety and efficacy for PDV by installation of activable mechanisms for self-destruction and spontaneous light-emission.

The pig as a model for therapeutic human anti-cancer vaccine development, elucidating the T-cell reactivity against IDO and RhoC

DEFF Research Database (Denmark)

Overgaard, Nana Haahr; Frøsig, Thomas Mørch; Welner, Simon

is important. Previous development of therapeutic cancer vaccines has largely been based on studies in mice and the majority of these candidate vaccines failed to establish therapeutic responses in subsequent human clinical trials. Since the porcine immunome is more closely related to the human counterpart, we...... here introduce pigs as a superior large animal model for human cancer vaccine development via the use of our unique technology for swine leukocyte antigen (SLA) production. IDO and RhoC, both known to be important in human cancer development and progression, were used as vaccine targets. Pigs were......, and peptide-SLA complex stability measurements revealed 89 stable (t½ ≥ 0.5 hour) complexes. Vaccine-induced peptide-specific CTL responses were monitored using IFN-γ release as a read out. We found responses to IDO- and RhoC-derived peptides across all groups; surprisingly non-stably binding peptides also...

Next-Generation Dengue Vaccines: Novel Strategies Currently Under Development

Directory of Open Access Journals (Sweden)

Anna P. Durbin

2011-09-01

Full Text Available Dengue has become the most important arboviral infection worldwide with more than 30 million cases of dengue fever estimated to occur each year. The need for a dengue vaccine is great and several live attenuated dengue candidate vaccines are proceeding through clinical evaluation. The need to induce a balanced immune response against all four DENV serotypes with a single vaccine has been a challenge for dengue vaccine developers. A live attenuated DENV chimeric vaccine produced by Sanofi Pasteur has recently entered Phase III evaluation in numerous dengue-endemic regions of the world. Viral interference between serotypes contained in live vaccines has required up to three doses of the vaccine be given over a 12-month period of time. For this reason, novel DENV candidate vaccines are being developed with the goal of achieving a protective immune response with an immunization schedule that can be given over the course of a few months. These next-generation candidates include DNA vaccines, recombinant adenovirus vectored vaccines, alphavirus replicons, and sub-unit protein vaccines. Several of these novel candidates will be discussed.

Next-generation dengue vaccines: novel strategies currently under development.

Science.gov (United States)

Durbin, Anna P; Whitehead, Stephen S

2011-10-01

Dengue has become the most important arboviral infection worldwide with more than 30 million cases of dengue fever estimated to occur each year. The need for a dengue vaccine is great and several live attenuated dengue candidate vaccines are proceeding through clinical evaluation. The need to induce a balanced immune response against all four DENV serotypes with a single vaccine has been a challenge for dengue vaccine developers. A live attenuated DENV chimeric vaccine produced by Sanofi Pasteur has recently entered Phase III evaluation in numerous dengue-endemic regions of the world. Viral interference between serotypes contained in live vaccines has required up to three doses of the vaccine be given over a 12-month period of time. For this reason, novel DENV candidate vaccines are being developed with the goal of achieving a protective immune response with an immunization schedule that can be given over the course of a few months. These next-generation candidates include DNA vaccines, recombinant adenovirus vectored vaccines, alphavirus replicons, and sub-unit protein vaccines. Several of these novel candidates will be discussed.

A History of the Development of Brucella Vaccines

Directory of Open Access Journals (Sweden)

Eric Daniel Avila-Calderón

2013-01-01

Full Text Available Brucellosis is a worldwide zoonosis affecting animal and human health. In the last several decades, much research has been performed to develop safer Brucella vaccines to control the disease mainly in animals. Till now, no effective human vaccine is available. The aim of this paper is to review and discuss the importance of methodologies used to develop Brucella vaccines in pursuing this challenge.

Guiding dengue vaccine development using knowledge gained from the success of the yellow fever vaccine.

Science.gov (United States)

Liang, Huabin; Lee, Min; Jin, Xia

2016-01-01

Flaviviruses comprise approximately 70 closely related RNA viruses. These include several mosquito-borne pathogens, such as yellow fever virus (YFV), dengue virus (DENV), and Japanese encephalitis virus (JEV), which can cause significant human diseases and thus are of great medical importance. Vaccines against both YFV and JEV have been used successfully in humans for decades; however, the development of a DENV vaccine has encountered considerable obstacles. Here, we review the protective immune responses elicited by the vaccine against YFV to provide some insights into the development of a protective DENV vaccine.

Establishing Correlates of Protection for Vaccine Development: Considerations for the Respiratory Syncytial Virus Vaccine Field.

Science.gov (United States)

Kulkarni, Prasad S; Hurwitz, Julia L; Simões, Eric A F; Piedra, Pedro A

2018-03-01

Correlates of protection (CoPs) can play a significant role in vaccine development by assisting the selection of vaccine candidates for clinical trials, supporting clinical trial design and implementation, and simplifying tests of vaccine modifications. Because of this important role in vaccine development, it is essential that CoPs be defined by well-designed immunogenicity and efficacy studies, with attention paid to benefits and limitations. The respiratory syncytial virus (RSV) field is unique in that a great deal of information about the humoral response is available from basic research and clinical studies. Polyclonal and monoclonal antibodies have been used routinely in the clinic to protect vulnerable infants from infection, providing a wealth of information about correlations between neutralizing antibodies and disease prevention. Considerations for the establishment of future CoPs to support RSV vaccine development in different populations are therefore discussed.

Recent progress in West Nile virus diagnosis and vaccination

Directory of Open Access Journals (Sweden)

De Filette Marina

2012-03-01

Full Text Available Abstract West Nile virus (WNV is a positive-stranded RNA virus belonging to the Flaviviridae family, a large family with 3 main genera (flavivirus, hepacivirus and pestivirus. Among these viruses, there are several globally relevant human pathogens including the mosquito-borne dengue virus (DENV, yellow fever virus (YFV, Japanese encephalitis virus (JEV and West Nile virus (WNV, as well as tick-borne viruses such as tick-borne encephalitis virus (TBEV. Since the mid-1990s, outbreaks of WN fever and encephalitis have occurred throughout the world and WNV is now endemic in Africa, Asia, Australia, the Middle East, Europe and the Unites States. This review describes the molecular virology, epidemiology, pathogenesis, and highlights recent progress regarding diagnosis and vaccination against WNV infections.

Recent advances in recombinant protein-based malaria vaccines

DEFF Research Database (Denmark)

Draper, Simon J; Angov, Evelina; Horii, Toshihiro

2015-01-01

Plasmodium parasites are the causative agent of human malaria, and the development of a highly effective vaccine against infection, disease and transmission remains a key priority. It is widely established that multiple stages of the parasite's complex lifecycle within the human host and mosquito...... vector are susceptible to vaccine-induced antibodies. The mainstay approach to antibody induction by subunit vaccination has been the delivery of protein antigen formulated in adjuvant. Extensive efforts have been made in this endeavor with respect to malaria vaccine development, especially with regard......, with the prospects for the development of a highly effective multi-component/multi-stage/multi-antigen formulation seeming ever more likely. This review will focus on recent progress in protein vaccine design, development and/or clinical testing for a number of leading malaria antigens from the sporozoite...

Malaria Vaccine Development: The Need for Novel Approach-es: A Review Article

Directory of Open Access Journals (Sweden)

Shima MAHMOUDI

2018-03-01

Full Text Available Background: Although rigorous efforts have substantially decreased the malaria burden through decades, it still threatens the lives of millions of children. Development of an effective vaccine can provide important approach in malaria control strategies. Unfortunately, development of an effective vaccine for falciparum malaria has been hindered by the extreme complexity of malaria parasite biology, complex and diverse parasite genomes, and immune evasion by the parasites as well as the intricate nature of the parasites infection cycle. The aim of this review was to discuss the different approaches to malaria vaccine development until now.Methods: Scientific databases, including MEDLINE (via PubMed and SCOPUS were searched up to 30 Jan 2017 and the articles regarding malaria vaccine development were taken into examination.Results: Several strategies for malaria vaccine development including pre-erythrocytic vaccines, antibody-based subunit vaccines, vectored vaccines, whole sporozoite vaccines, genetically Attenuated parasites and sporozoite subunit vaccine, erythrocytic vaccines, sexual stage vaccine, transmission-blocking vaccine as well as synthetic peptides and conjugate vaccine has been introduced. However, the success has been limited thus far.Conclusion: Although development of malaria vaccine over the past 70 year has been continued, the discovery, development, and licensing of a malaria vaccine formulation, which meets safety, affordability, accessibility, applicability, and efficacy has not yet been achieved.

Buccal and sublingual vaccine delivery.

Science.gov (United States)

Kraan, Heleen; Vrieling, Hilde; Czerkinsky, Cecil; Jiskoot, Wim; Kersten, Gideon; Amorij, Jean-Pierre

2014-09-28

Because of their large surface area and immunological competence, mucosal tissues are attractive administration and target sites for vaccination. An important characteristic of mucosal vaccination is its ability to elicit local immune responses, which act against infection at the site of pathogen entry. However, mucosal surfaces are endowed with potent and sophisticated tolerance mechanisms to prevent the immune system from overreacting to the many environmental antigens. Hence, mucosal vaccination may suppress the immune system instead of induce a protective immune response. Therefore, mucosal adjuvants and/or special antigen delivery systems as well as appropriate dosage forms are required in order to develop potent mucosal vaccines. Whereas oral, nasal and pulmonary vaccine delivery strategies have been described extensively, the sublingual and buccal routes have received considerably less attention. In this review, the characteristics of and approaches for sublingual and buccal vaccine delivery are described and compared with other mucosal vaccine delivery sites. We discuss recent progress and highlight promising developments in the search for vaccine formulations, including adjuvants and suitable dosage forms, which are likely critical for designing a successful sublingual or buccal vaccine. Finally, we outline the challenges, hurdles to overcome and formulation issues relevant for sublingual or buccal vaccine delivery. Copyright © 2014. Published by Elsevier B.V.

Veterinary vaccines against Toxoplasma gondii

Directory of Open Access Journals (Sweden)

Elisabeth A Innes

2009-03-01

Full Text Available Toxoplasma gondii has a very wide intermediate host range and is thought to be able to infect all warm blooded animals. The parasite causes a spectrum of different diseases and clinical symptoms within the intermediate hosts and following infection most animals develop adaptive humoral and cell-mediated immune responses. The development of protective immunity to T. gondii following natural infection in many host species has led researchers to look at vaccination as a strategy to control disease, parasite multiplication and establishment in animal hosts. A range of different veterinary vaccines are required to help control T. gondii infection which include vaccines to prevent congenital toxoplasmosis, reduce or eliminate tissue cysts in meat producing animals and to prevent oocyst shedding in cats. In this paper we will discuss some of the history, challenges and progress in the development of veterinary vaccines against T. gondii.

Development of Burkholderia mallei and pseudomallei vaccines

Science.gov (United States)

Silva, Ediane B.; Dow, Steven W.

2013-01-01

Burkholderia mallei and Burkholderia pseudomallei are Gram-negative bacteria that cause glanders and melioidosis, respectively. Inhalational infection with either organism can result in severe and rapidly fatal pneumonia. Inoculation by the oral and cutaneous routes can also produce infection. Chronic infection may develop after recovery from acute infection with both agents, and control of infection with antibiotics requires prolonged treatment. Symptoms for both meliodosis and glanders are non-specific, making diagnosis difficult. B. pseudomallei can be located in the environment, but in the host, B. mallei and B. psedomallei are intracellular organisms, and infection results in similar immune responses to both agents. Effective early innate immune responses are critical to controlling the early phase of the infection. Innate immune signaling molecules such as TLR, NOD, MyD88, and pro-inflammatory cytokines such as IFN-γ and TNF-α play key roles in regulating control of infection. Neutrophils and monocytes are critical cells in the early infection for both microorganisms. Both monocytes and macrophages are necessary for limiting dissemination of B. pseudomallei. In contrast, the role of adaptive immune responses in controlling Burkholderia infection is less well understood. However, T cell responses are critical for vaccine protection from Burkholderia infection. At present, effective vaccines for prevention of glanders or meliodosis have not been developed, although recently development of Burkholderia vaccines has received renewed attention. This review will summarize current and past approaches to develop B. mallei and B. pseudomalllei vaccines, with emphasis on immune mechanisms of protection and the challenges facing the field. At present, immunization with live attenuated bacteria provides the most effective and durable immunity, and it is important therefore to understand the immune correlates of protection induced by live attenuated vaccines. Subunit

Universal Influenza Vaccines, a Dream to Be Realized Soon

Directory of Open Access Journals (Sweden)

Han Zhang

2014-04-01

Full Text Available Due to frequent viral antigenic change, current influenza vaccines need to be re-formulated annually to match the circulating strains for battling seasonal influenza epidemics. These vaccines are also ineffective in preventing occasional outbreaks of new influenza pandemic viruses. All these challenges call for the development of universal influenza vaccines capable of conferring broad cross-protection against multiple subtypes of influenza A viruses. Facilitated by the advancement in modern molecular biology, delicate antigen design becomes one of the most effective factors for fulfilling such goals. Conserved epitopes residing in virus surface proteins including influenza matrix protein 2 and the stalk domain of the hemagglutinin draw general interest for improved antigen design. The present review summarizes the recent progress in such endeavors and also covers the encouraging progress in integrated antigen/adjuvant delivery and controlled release technology that facilitate the development of an affordable universal influenza vaccine.

Development of a Vaccine for Eradicating Contagious Bovine ...

International Development Research Centre (IDRC) Digital Library (Canada)

Since eventual success depends on the vaccine's acceptability by livestock keepers, the project involves them in field-testing and assesses their willingness to pay for the vaccine. The project also ... Outputs. Studies. Developing vaccines for animals, the case of Contagious Bovine Pleuropneumonia (CBPP) in Africa. 53232.

Meningococcal group B vaccines.

Science.gov (United States)

Findlow, Jamie

2013-06-01

Meningococcal disease remains a devastating and feared infection with a significant morbidity and mortality profile. The successful impact of meningococcal capsular group C glyconconjugate vaccines introduced into the UK infant immunization schedule in 1999, has resulted in >80% of disease now being attributable to meningococcal capsular group B (MenB). MenB glyconconjugate vaccines are not immunogenic and hence, vaccine design has focused on sub-capsular antigens. Recently, a four component vaccine to combat MenB disease (4CMenB) has progressed through clinical development and was approved by the European Medicines Agency at the end of 2012. This vaccine has proven safe and immunogenic and has been predicted to provide protection against ~73% of the MenB disease from England and Wales. Recommendation/implementation of the vaccine into the UK infant schedule is currently being evaluated. 4CMenB has the potential to provide protection against a significant proportion of MenB disease in the UK which is currently unpreventable.

Status of vaccine research and development for Shigella.

Science.gov (United States)

Mani, Sachin; Wierzba, Thomas; Walker, Richard I

2016-06-03

Shigella are gram-negative bacteria that cause severe diarrhea and dysentery. In 2013, Shigella infections caused an estimated 34,400 deaths in children less than five years old and, in 2010, an estimated 40,000 deaths in persons older than five years globally. New disease burden estimates from newly deployed molecular diagnostic assays with increased sensitivity suggest that Shigella-associated morbidity may be much greater than previous disease estimates from culture-based methods. Primary prevention of this disease should be based on universal provision of potable water and sanitation methods and improved personal and food hygiene. However, an efficacious and low-cost vaccine would complement and accelerate disease reduction while waiting for universal access to water, sanitation, and hygiene improvements. This review article provides a landscape of Shigella vaccine development efforts. No vaccine is yet available, but human and animal challenge-rechallenge trials with virulent Shigella as well as observational studies in Shigella-endemic areas have shown that the incidence of disease decreases following Shigella infection, pointing to biological feasibility of a vaccine. Immunity to Shigella appears to be strain-specific, so a vaccine that covers the most commonly detected strains (i.e., S. flexneri 2a, 3a, 6, and S. sonnei) or a vaccine using cross-species conserved antigens would likely be most effective. Vaccine development and testing may be accelerated by use of animal models, such as the guinea pig keratoconjunctivitis or murine pneumonia models. Because there is no correlate of protection, however, human studies will be necessary to evaluate vaccine efficacy prior to deployment. A diversity of Shigella vaccine constructs are under development, including live attenuated, formalin-killed whole-cell, glycoconjugate, subunit, and novel antigen vaccines (e.g., Type III secretion system and outer membrane proteins). Copyright © 2016 World Health Organization

Development and validation of an attenuated Mycoplasma hyopneumoniae aerosol vaccine.

Science.gov (United States)

Feng, Zhi-Xin; Wei, Yan-Na; Li, Gui-Lan; Lu, Xiao-Ming; Wan, Xiu-Feng; Pharr, G Todd; Wang, Zhan-Wei; Kong, Meng; Gan, Yuan; Bai, Fang-Fang; Liu, Mao-Jun; Xiong, Qi-Yan; Wu, Xu-Su; Shao, Guo-Qing

2013-12-27

Mycoplasma hyopneumoniae (M. hyopneumoniae) causes a chronic respiratory disease with high morbidity and low mortality in swine, and has been presented as a major cause of growth retardation in the swine industry. Aerosol vaccination presents a needle free, high throughput, and efficient platform for vaccine delivery, and has been widely applied in poultry vaccination. However, aerosol vaccines have rarely been used in swine vaccination primarily because the long and curving respiratory track of swine presents a barrier for vaccine particle delivery. To develop an effective M. hyopneumoniae aerosol vaccine, three major barriers need to be overcome: to optimize particle size for aerosol delivery, to maintain the viability of mycoplasma cells in the vaccine, and to optimize the environmental conditions for vaccine delivery. In this study, an aerosol mycoplasma vaccine was successfully developed based on a conventional live attenuated M. hyopneumoniae vaccine. Specifically, the Pari LCD nebulizer was used to produce an aerosol vaccine particle size less than 5 μm; and a buffer with 5% glycerol was developed and optimized to prevent inactivation of M. hyopneumoniae caused by aerosolization and evaporation. Before nebulization, the room temperature and relative humidity were control to 20-25 °C and 70-75%, respectively, which helped maintain the viability of aerosol vaccine. Animal experiments demonstrated that this newly developed aerosol vaccine was effectively delivered to swine low respiratory track, being confirmed by nested-PCR, in situ hybridization and scanning electron microscope. Moreover, M. hyopneumoniae specific sIgA secretion was detected in the nasal swab samples at 14 days post-immunization. To our knowledge, this is the first report on a live M. hyopneumoniae aerosol vaccine. Copyright © 2013 Elsevier B.V. All rights reserved.

A History of the Development of Brucella Vaccines

OpenAIRE

Avila-Calder?n, Eric Daniel; Lopez-Merino, Ahid?; Sriranganathan, Nammalwar; Boyle, Stephen M.; Contreras-Rodr?guez, Araceli

2013-01-01

Brucellosis is a worldwide zoonosis affecting animal and human health. In the last several decades, much research has been performed to develop safer Brucella vaccines to control the disease mainly in animals. Till now, no effective human vaccine is available. The aim of this paper is to review and discuss the importance of methodologies used to develop Brucella vaccines in pursuing this challenge. CONACYT CB-2011-01, 169259 SIP-IPN 20110891, 20134610 ICYTDF-IPN (Project of Investiga...

Gene-based vaccine development for improving animal production in developing countries. Possibilities and constraints

International Nuclear Information System (INIS)

Egerton, J.R.

2005-01-01

For vaccine production, recombinant antigens must be protective. Identifying protective antigens or candidate antigens is an essential precursor to vaccine development. Even when a protective antigen has been identified, cloning of its gene does not lead directly to vaccine development. The fimbrial protein of Dichelobacter nodosus, the agent of foot-rot in ruminants, was known to be protective. Recombinant vaccines against this infection are ineffective if expressed protein subunits are not assembled as mature fimbriae. Antigenic competition between different, but closely related, recombinant antigens limited the use of multivalent vaccines based on this technology. Recombinant antigens may need adjuvants to enhance response. DNA vaccines, potentiated with genes for different cytokines, may replace the need for aggressive adjuvants, and especially where cellular immunity is essential for protection. The expression of antigens from animal pathogens in plants and the demonstration of some immunity to a disease like rinderpest after ingestion of these, suggests an alternative approach to vaccination by injection. Research on disease pathogenesis and the identification of candidate antigens is specific to the disease agent. The definition of expression systems and the formulation of a vaccine for each disease must be followed by research to establish safety and efficacy. Where vaccines are based on unique gene sequences, the intellectual property is likely to be protected by patent. Organizations, licensed to produce recombinant vaccines, expect to recover their costs and to make a profit. The consequence is that genetically-derived vaccines are expensive. The capacity of vaccines to help animal owners of poorer countries depends not only on quality and cost but also on the veterinary infrastructure where they are used. Ensuring the existence of an effective animal health infrastructure in developing countries is as great a challenge for the developed world as

Working towards dengue as a vaccine-preventable disease: challenges and opportunities.

Science.gov (United States)

Shrivastava, Ambuj; Tripathi, Nagesh K; Dash, Paban K; Parida, Manmohan

2017-10-01

Dengue is an emerging viral disease that affects the human population around the globe. Recent advancements in dengue virus research have opened new avenues for the development of vaccines against dengue. The development of a vaccine against dengue is a challenging task because any of the four serotypes of dengue viruses can cause disease. The development of a dengue vaccine aims to provide balanced protection against all the serotypes. Several dengue vaccine candidates are in the developmental stages such as inactivated, live attenuated, recombinant subunit, and plasmid DNA vaccines. Area covered: The authors provide an overview of the progress made in the development of much needed dengue vaccines. The authors include their expert opinion and their perspectives for future developments. Expert opinion: Human trials of a live attenuated tetravalent chimeric vaccine have clearly demonstrated its potential as a dengue vaccine. Other vaccine candidate molecules such as DENVax, a recombinant chimeric vaccine andTetraVax, are at different stages of development at this time. The authors believe that the novel strategies for testing and improving the immune response of vaccine candidates in humans will eventually lead to the development of a successful dengue vaccine in future.

Lactobacilli as live vaccine delivery vectors: Progress and prospects

NARCIS (Netherlands)

Seegers, J.F.M.L.

2002-01-01

Evidence is accumulating that lactobacilli influence the immune response in a strain-dependent manner. This immunomodulatory capacity is important for the development of the immune response, and also identifies Lactobacillus as a potent oral vaccine carrier. Most of our current knowledge of the use

Novel Platforms for the Development of a Universal Influenza Vaccine

Directory of Open Access Journals (Sweden)

Arun Kumar

2018-03-01

Full Text Available Despite advancements in immunotherapeutic approaches, influenza continues to cause severe illness, particularly among immunocompromised individuals, young children, and elderly adults. Vaccination is the most effective way to reduce rates of morbidity and mortality caused by influenza viruses. Frequent genetic shift and drift among influenza-virus strains with the resultant disparity between circulating and vaccine virus strains limits the effectiveness of the available conventional influenza vaccines. One approach to overcome this limitation is to develop a universal influenza vaccine that could provide protection against all subtypes of influenza viruses. Moreover, the development of a novel or improved universal influenza vaccines may be greatly facilitated by new technologies including virus-like particles, T-cell-inducing peptides and recombinant proteins, synthetic viruses, broadly neutralizing antibodies, and nucleic acid-based vaccines. This review discusses recent scientific advances in the development of next-generation universal influenza vaccines.

Epidemiological Studies to Support the Development of Next Generation Influenza Vaccines.

Science.gov (United States)

Petrie, Joshua G; Gordon, Aubree

2018-03-26

The National Institute of Allergy and Infectious Diseases recently published a strategic plan for the development of a universal influenza vaccine. This plan focuses on improving understanding of influenza infection, the development of influenza immunity, and rational design of new vaccines. Epidemiological studies such as prospective, longitudinal cohort studies are essential to the completion of these objectives. In this review, we discuss the contributions of epidemiological studies to our current knowledge of vaccines and correlates of immunity, and how they can contribute to the development and evaluation of the next generation of influenza vaccines. These studies have been critical in monitoring the effectiveness of current influenza vaccines, identifying issues such as low vaccine effectiveness, reduced effectiveness among those who receive repeated vaccination, and issues related to egg adaptation during the manufacturing process. Epidemiological studies have also identified population-level correlates of protection that can inform the design and development of next generation influenza vaccines. Going forward, there is an enduring need for epidemiological studies to continue advancing knowledge of correlates of protection and the development of immunity, to evaluate and monitor the effectiveness of next generation influenza vaccines, and to inform recommendations for their use.

VACCINES AND IMMUNIZATION: WORLD SITUATION

Directory of Open Access Journals (Sweden)

G.H. Brundtland

2007-01-01

Full Text Available The last issue of the report «vaccines and immunization: world situation» stresses considerable success in immunization at the global level since the mid 90 s — completely total eradication of poliomyelitis across the world, as well as the drastic reduction of the new measles and tetanus cases among mothers and newborns in some poor countries. The report also briefly describes the progress in the development and implementation of the new life saving vaccines, which may save millions of lives annually. The authors have explained some of the reasons, why the global community should invest in immunization, as well as the perspectives for the use of vaccines and immunization in future.Key words: vaccine, immunization, children.

"Communicate to vaccinate": the development of a taxonomy of communication interventions to improve routine childhood vaccination.

Science.gov (United States)

Willis, Natalie; Hill, Sophie; Kaufman, Jessica; Lewin, Simon; Kis-Rigo, John; De Castro Freire, Sara Bensaude; Bosch-Capblanch, Xavier; Glenton, Claire; Lin, Vivian; Robinson, Priscilla; Wiysonge, Charles S

2013-05-11

Vaccination is a cost-effective public health measure and is central to the Millennium Development Goal of reducing child mortality. However, childhood vaccination coverage remains sub-optimal in many settings. While communication is a key feature of vaccination programmes, we are not aware of any comprehensive approach to organising the broad range of communication interventions that can be delivered to parents and communities to improve vaccination coverage. Developing a classification system (taxonomy) organised into conceptually similar categories will aid in: understanding the relationships between different types of communication interventions; facilitating conceptual mapping of these interventions; clarifying the key purposes and features of interventions to aid implementation and evaluation; and identifying areas where evidence is strong and where there are gaps. This paper reports on the development of the 'Communicate to vaccinate' taxonomy. The taxonomy was developed in two stages. Stage 1 included: 1) forming an advisory group; 2) searching for descriptions of interventions in trials (CENTRAL database) and general health literature (Medline); 3) developing a sampling strategy; 4) screening the search results; 5) developing a data extraction form; and 6) extracting intervention data. Stage 2 included: 1) grouping the interventions according to purpose; 2) holding deliberative forums in English and French with key vaccination stakeholders to gather feedback; 3) conducting a targeted search of grey literature to supplement the taxonomy; 4) finalising the taxonomy based on the input provided. The taxonomy includes seven main categories of communication interventions: inform or educate, remind or recall, teach skills, provide support, facilitate decision making, enable communication and enhance community ownership. These categories are broken down into 43 intervention types across three target groups: parents or soon-to-be-parents; communities, community

Next-Generation Dengue Vaccines: Novel Strategies Currently Under Development

OpenAIRE

Anna P. Durbin; Stephen S. Whitehead

2011-01-01

Dengue has become the most important arboviral infection worldwide with more than 30 million cases of dengue fever estimated to occur each year. The need for a dengue vaccine is great and several live attenuated dengue candidate vaccines are proceeding through clinical evaluation. The need to induce a balanced immune response against all four DENV serotypes with a single vaccine has been a challenge for dengue vaccine developers. A live attenuated DENV chimeric vaccine produced by Sanofi Past...

Intellectual property rights and challenges for development of affordable human papillomavirus, rotavirus and pneumococcal vaccines: Patent landscaping and perspectives of developing country vaccine manufacturers.

Science.gov (United States)

Chandrasekharan, Subhashini; Amin, Tahir; Kim, Joyce; Furrer, Eliane; Matterson, Anna-Carin; Schwalbe, Nina; Nguyen, Aurélia

2015-11-17

The success of Gavi, the Vaccine Alliance depends on the vaccine markets providing appropriate, affordable vaccines at sufficient and reliable quantities. Gavi's current supplier base for new and underutilized vaccines, such as the human papillomavirus (HPV), rotavirus, and the pneumococcal conjugate vaccine is very small. There is growing concern that following globalization of laws on intellectual property rights (IPRs) through trade agreements, IPRs are impeding new manufacturers from entering the market with competing vaccines. This article examines the extent to which IPRs, specifically patents, can create such obstacles, in particular for developing country vaccine manufacturers (DCVMs). Through building patent landscapes in Brazil, China, and India and interviews with manufacturers and experts in the field, we found intense patenting activity for the HPV and pneumococcal vaccines that could potentially delay the entry of new manufacturers. Increased transparency around patenting of vaccine technologies, stricter patentability criteria suited for local development needs and strengthening of IPRs management capabilities where relevant, may help reduce impediments to market entry for new manufacturers and ensure a competitive supplier base for quality vaccines at sustainably low prices. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Strategies & recent development of transmission-blocking vaccines against Plasmodium falciparum

Directory of Open Access Journals (Sweden)

Neha Chaturvedi

2016-01-01

Full Text Available Transmission blocking malaria vaccines are aimed to block the development and maturity of sexual stages of parasite within mosquitoes. The vaccine candidate antigens (Pfs25, Pfs48/45, Pfs230 that have shown transmission blocking immunity in model systems are in different stages of development. These antigens are immunogenic with limited genetic diversity. Pfs25 is a leading candidate and currently in phase I clinical trial. Efforts are now focused on the cost-effective production of potent antigens using safe adjuvants and optimization of vaccine delivery system that are capable of inducing strong immune responses. This review addresses the potential usefulness, development strategies, challenges, clinical trials and current status of Plasmodium falciparum sexual stage malaria vaccine candidate antigens for the development of transmission-blocking vaccines.

A multilateral effort to develop DNA vaccines against falciparum malaria.

Science.gov (United States)

Kumar, Sanjai; Epstein, Judith E; Richie, Thomas L; Nkrumah, Francis K; Soisson, Lorraine; Carucci, Daniel J; Hoffman, Stephen L

2002-03-01

Scientists from several organizations worldwide are working together to develop a multistage, multigene DNA-based vaccine against Plasmodium falciparum malaria. This collaborative vaccine development effort is named Multi-Stage DNA-based Malaria Vaccine Operation. An advisory board of international experts in vaccinology, malariology and field trials provides the scientific oversight to support the operation. This article discusses the rationale for the approach, underlying concepts and the pre-clinical development process, and provides a brief outline of the plans for the clinical testing of a multistage, multiantigen malaria vaccine based on DNA plasmid immunization technology.

Considerations for the rational design of a Chlamydia vaccine.

Science.gov (United States)

Liang, Steven; Bulir, David; Kaushic, Charu; Mahony, James

2017-04-03

Chlamydia trachomatis is the leading cause of preventable blindness and the most common bacterial sexually transmitted infection. Remarkable progress in vaccine research over the past six decades has led to the advancement of novel C. trachomatis vaccine candidates into clinical trials. However, many questions regarding the role of specific cellular populations and molecular mechanisms in protective immunity against human C. trachomatis genital tract infections remain unanswered. Biomarkers of vaccine induced protective immunity are elusive in humans, while a cautionary message on the translatability of data obtained from current animal models has emanated from vaccine research and development efforts against other important human pathogens. In this commentary, we highlight recent advances in Chlamydia vaccine development and discuss their implications in the context of a rational approach to the design of a human C. trachomatis vaccine.

Shigella vaccine development: prospective animal models and current status.

Science.gov (United States)

Kim, Yeon-Jeong; Yeo, Sang-Gu; Park, Jae-Hak; Ko, Hyun-Jeong

2013-01-01

Shigella was first discovered in 1897 and is a major causative agent of dysenteric diarrhea. The number of affected patients has decreased globally because of improved sanitary conditions; however, Shigella still causes serious problems in many subjects, including young children and the elderly, especially in developing countries. Although antibiotics may be effective, a vaccine would be the most powerful solution to combat shigellosis because of the emergence of drug-resistant strains. However, the development of a vaccine is hampered by several problems. First, there is no suitable animal model that can replace human-based studies for the investigation of the in vivo mechanisms of Shigella vaccines. Mouse, guinea pig, rat, rabbit, and nonhuman primates could be used as models for shigellosis, but they do not represent human shigellosis and each has its own weaknesses. However, a recent murine model based on peritoneal infection with virulent S. flexneri 2a is promising. Moreover, although the inflammatory responses and mechanisms such as pathogenassociated molecular patterns and danger-associated molecular patterns have been studied, the pathology and immunology of Shigella are still not clearly defined. Despite these obstacles, many vaccine candidates have been developed, including live attenuated, killed whole cells, conjugated, and subunit vaccines. The development of Shigella vaccines also demands considerations of the cost, routes of administration, ease of storage (stability), cross-reactivity, safety, and immunogenicity. The main aim of this review is to provide a detailed introduction to the many promising vaccine candidates and animal models currently available, including the newly developed mouse model.

Vaccine development for emerging virulent infectious diseases.

Science.gov (United States)

Maslow, Joel N

2017-10-04

The recent outbreak of Zaire Ebola virus in West Africa altered the classical paradigm of vaccine development and that for emerging infectious diseases (EIDs) in general. In this paper, the precepts of vaccine discovery and advancement through pre-clinical and clinical assessment are discussed in the context of the recent Ebola virus, Middle East Respiratory Syndrome coronavirus (MERS-CoV), and Zika virus outbreaks. Clinical trial design for diseases with high mortality rates and/or high morbidity in the face of a global perception of immediate need and the factors that drive design in the face of a changing epidemiology are presented. Vaccines for EIDs thus present a unique paradigm to standard development precepts. Copyright © 2017 Elsevier Ltd. All rights reserved.

A potential disruptive technology in vaccine development: gene-based vaccines and their application to infectious diseases.

Science.gov (United States)

Kaslow, David C

2004-10-01

Vaccine development requires an amalgamation of disparate disciplines and has unique economic and regulatory drivers. Non-viral gene-based delivery systems, such as formulated plasmid DNA, are new and potentially disruptive technologies capable of providing 'cheaper, simpler, and more convenient-to-use' vaccines. Typically and somewhat ironically, disruptive technologies have poorer product performance, at least in the near-term, compared with the existing conventional technologies. Because successful product development requires that the product's performance must meet or exceed the efficacy threshold for a desired application, the appropriate selection of the initial product applications for a disruptive technology is critical for its successful evolution. In this regard, the near-term successes of gene-based vaccines will likely be for protection against bacterial toxins and acute viral and bacterial infections. Recent breakthroughs, however, herald increasing rather than languishing performance improvements in the efficacy of gene-based vaccines. Whether gene-based vaccines ultimately succeed in eliciting protective immunity in humans to persistent intracellular pathogens, such as HIV, malaria and tuberculosis, for which the conventional vaccine technologies have failed, remains to be determined. A success against any one of the persistent intracellular pathogens would be sufficient proof that gene-based vaccines represent a disruptive technology against which future vaccine technologies will be measured.

Delivering vaccines to the people who need them most.

Science.gov (United States)

Barocchi, Michèle Anne; Rappuoli, Rino

2015-06-19

Thanks to the Global Alliance for Vaccines and Immunization (GAVI), the Vaccine Fund and the Bill & Melinda Gates Foundation, the global health community has made enormous progress in providing already existing vaccines to developing countries. However, there still exists a gap to develop vaccines for which there is no market in the Western world, owing to low economic incentives for the private sector to justify the investments necessary for vaccine development. In many cases, industry has the technologies, but lacks the impetus to direct resources to develop these vaccine products. The present emergency with the Ebola vaccine provides us an excellent example where a vaccine was feasible several years ago, but the global health community waited for a humanitarian disaster to direct efforts and resources to develop this vaccine. In the beginning of 2015, the first large-scale trials of two experimental vaccines against Ebola virus disease have begun in West Africa. During the past few years, several institutions have dedicated efforts to the development of vaccines against diseases present only in low-income countries. These include the International Vaccine Institute, the Novartis Vaccines Institute for Global Health, the Hilleman Institute, the Sabin Vaccine Institute and the Infectious Disease Research Institute. Nevertheless, solving this problem requires a more significant global effort than that currently invested. These efforts include a clear policy, global coordination of funds dedicated to the development of neglected disease and an agreement on regulatory strategies and incentives for the private sector. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Vaccines in Development against West Nile Virus

Directory of Open Access Journals (Sweden)

Frederic Tangy

2013-09-01

Full Text Available West Nile encephalitis emerged in 1999 in the United States, then rapidly spread through the North American continent causing severe disease in human and horses. Since then, outbreaks appeared in Europe, and in 2012, the United States experienced a new severe outbreak reporting a total of 5,387 cases of West Nile virus (WNV disease in humans, including 243 deaths. So far, no human vaccine is available to control new WNV outbreaks and to avoid worldwide spreading. In this review, we discuss the state-of-the-art of West Nile vaccine development and the potential of a novel safe and effective approach based on recombinant live attenuated measles virus (MV vaccine. MV vaccine is a live attenuated negative-stranded RNA virus proven as one of the safest, most stable and effective human vaccines. We previously described a vector derived from the Schwarz MV vaccine strain that stably expresses antigens from emerging arboviruses, such as dengue, West Nile or chikungunya viruses, and is strongly immunogenic in animal models, even in the presence of MV pre-existing immunity. A single administration of a recombinant MV vaccine expressing the secreted form of WNV envelope glycoprotein elicited protective immunity in mice and non-human primates as early as two weeks after immunization, indicating its potential as a human vaccine.

Killed oral cholera vaccines: history, development and implementation challenges.

Science.gov (United States)

Lopez, Anna Lena; Gonzales, Maria Liza Antoinette; Aldaba, Josephine G; Nair, G Balakrish

2014-09-01

Cholera is still a major global health problem, affecting mainly people living in unsanitary conditions and who are at risk for outbreaks of cholera. During the past decade, outbreaks are increasingly reported from more countries. From the early killed oral cholera vaccine, rapid improvements in vaccine development occurred as a result of a better understanding of the epidemiology of the disease, pathogenesis of cholera infection and immunity. The newer-generation oral killed cholera vaccines have been shown to be safe and effective in field trials conducted in cholera endemic areas. Likewise, they have been shown to be protective when used during outbreak settings. Aside from providing direct protection to vaccinated individuals, recent studies have demonstrated that these killed oral vaccines also confer indirect protection through herd immunity. Although new-generation oral cholera vaccines should not be considered in isolation from other preventive approaches in countries where they are most needed, especially improved water quality and sanitation, these vaccines serve as immediately available public health tools for preventing further morbidity and mortality from cholera. However, despite its availability for more than two decades, use of these vaccines has not been optimized. Although there are limitations of the currently available oral cholera vaccines, recent data show that the vaccines are safe, feasible to use even in difficult circumstances and able to provide protection in various settings. Clear identification of the areas and target population groups who will benefit from the use of the cholera vaccines will be required and strategies to facilitate accessibility and usage of these vaccines in these areas and population groups will need to be developed.

Progress on adenovirus-vectored universal influenza vaccines

OpenAIRE

Xiang, Kui; Ying, Guan; Yan, Zhou; Shanshan, Yan; Lei, Zhang; Hongjun, Li; Maosheng, Sun

2015-01-01

Influenza virus (IFV) infection causes serious health problems and heavy financial burdens each year worldwide. The classical inactivated influenza virus vaccine (IIVV) and live attenuated influenza vaccine (LAIV) must be updated regularly to match the new strains that evolve due to antigenic drift and antigenic shift. However, with the discovery of broadly neutralizing antibodies that recognize conserved antigens, and the CD8+ T cell responses targeting viral internal proteins nucleoprotein ...

The clinical development process for a novel preventive vaccine: An overview

Directory of Open Access Journals (Sweden)

K Singh

2016-01-01

Full Text Available Each novel vaccine candidate needs to be evaluated for safety, immunogenicity, and protective efficacy in humans before it is licensed for use. After initial safety evaluation in healthy adults, each vaccine candidate follows a unique development path. This article on clinical development gives an overview on the development path based on the expectations of various guidelines issued by the World Health Organization (WHO, the European Medicines Agency (EMA, and the United States Food and Drug Administration (USFDA. The manuscript describes the objectives, study populations, study designs, study site, and outcome(s of each phase (Phase I-III of a clinical trial. Examples from the clinical development of a malaria vaccine candidate, a rotavirus vaccine, and two vaccines approved for human papillomavirus (HPV have also been discussed. The article also tabulates relevant guidelines, which can be referred to while drafting the development path of a novel vaccine candidate.

Challenges and constraints to vaccination in developing countries.

Science.gov (United States)

Alders, R G; Bagnol, B; Young, M P; Ahlers, C; Brum, E; Rushton, J

2007-01-01

The challenges and constraints to vaccinating poultry in areas where adequate infrastructure and human resources are lacking are addressed in both a technical and a socioeconomic framework. The key issues discussed are: (1) selection of an appropriate vaccine and vaccination technique, including the advantages and disadvantages of a combined vaccine against highly pathogenic avian influenza (HPAI) and Newcastle disease and addressing the differences between endemic disease and emergency disease control; (2) vaccine conservation and distribution; (3) evaluation of the flocks to be vaccinated in terms of their disease status, immunocompetence and production systems; (4) design of effective information, education and communication materials and methods with and for veterinary and extension staff as well as commercial and smallholder producers and community vaccinators in rural areas; (5) evaluation and monitoring systems for technical and socioeconomic factors that affect vaccination; (6) support and coordination of and by relevant public and private agencies; (7) the role of simultaneous implementation of other control activities in addition to vaccination; (8) the importance of assessing the costs and cost-effectiveness of various approaches to the control of HPAI, including the prevention of other endemic killer diseases and options for cost-sharing; (9) evaluation of the incentives for poultry-holders, vaccinators and vaccine producers to contribute to and participate in effective vaccination campaigns; and (10) policy development and the organizational framework for short- and long-term implementation and communication to decision-makers.

Challenges and Future in Vaccines, Drug Development, and Immunomodulatory Therapy

Science.gov (United States)

Nau, Gerard J.; Ross, Ted M.; Evans, Thomas G.; Chakraborty, Krishnendu; Empey, Kerry M.; Flynn, JoAnne L.

2014-01-01

Pulmonary diseases and infections are among the top contributors to human morbidity and mortality worldwide, and despite the successful history of vaccines and antimicrobial therapeutics, infectious disease still presents a significant threat to human health. Effective vaccines are frequently unavailable in developing countries, and successful vaccines have yet to be developed for major global maladies, such as tuberculosis. Furthermore, antibiotic resistance poses a growing threat to human health. The “Challenges and Future in Vaccines, Drug Development, and Immunomodulatory Therapy” session of the 2013 Pittsburgh International Lung Conference highlighted several recent and current studies related to treatment and prevention of antibiotic-resistant bacterial infections, highly pathogenic influenza, respiratory syncytial virus, and tuberculosis. Research presented here focused on novel antimicrobial therapies, new vaccines that are either in development or currently in clinical trials, and the potential for immunomodulatory therapies. These studies are making important contributions to the areas of microbiology, virology, and immunology related to pulmonary diseases and infections and are paving the way for improvements in the efficacy of vaccines and antimicrobials. PMID:25148426

Challenges and future in vaccines, drug development, and immunomodulatory therapy.

Science.gov (United States)

Kling, Heather M; Nau, Gerard J; Ross, Ted M; Evans, Thomas G; Chakraborty, Krishnendu; Empey, Kerry M; Flynn, JoAnne L

2014-08-01

Pulmonary diseases and infections are among the top contributors to human morbidity and mortality worldwide, and despite the successful history of vaccines and antimicrobial therapeutics, infectious disease still presents a significant threat to human health. Effective vaccines are frequently unavailable in developing countries, and successful vaccines have yet to be developed for major global maladies, such as tuberculosis. Furthermore, antibiotic resistance poses a growing threat to human health. The "Challenges and Future in Vaccines, Drug Development, and Immunomodulatory Therapy" session of the 2013 Pittsburgh International Lung Conference highlighted several recent and current studies related to treatment and prevention of antibiotic-resistant bacterial infections, highly pathogenic influenza, respiratory syncytial virus, and tuberculosis. Research presented here focused on novel antimicrobial therapies, new vaccines that are either in development or currently in clinical trials, and the potential for immunomodulatory therapies. These studies are making important contributions to the areas of microbiology, virology, and immunology related to pulmonary diseases and infections and are paving the way for improvements in the efficacy of vaccines and antimicrobials.

What Has 30 Years of HIV Vaccine Research Taught Us?

Directory of Open Access Journals (Sweden)

José Esparza

2013-10-01

Full Text Available When HIV was discovered and established as the cause of AIDS in 1983–1984, many people believed that a vaccine would be rapidly developed. However, 30 years have passed and we are still struggling to develop an elusive vaccine. In trying to achieve that goal, different scientific paradigms have been explored. Although major progress has been made in understanding the scientific basis for HIV vaccine development, efficacy trials have been critical in moving the field forward. Major lessons learned are: the development of an HIV vaccine is an extremely difficult challenge; the temptation of just following the fashion should be avoided; clinical trials are critical, especially large-scale efficacy trials; HIV vaccine research will require long-term commitment; and sustainable collaborations are needed to accelerate the development of an HIV vaccine. Concrete actions must be implemented with the sense of urgency imposed by the severity of the AIDS epidemic.

Development of a chimeric Zika vaccine using a licensed live-attenuated flavivirus vaccine as backbone.

Science.gov (United States)

Li, Xiao-Feng; Dong, Hao-Long; Wang, Hong-Jiang; Huang, Xing-Yao; Qiu, Ye-Feng; Ji, Xue; Ye, Qing; Li, Chunfeng; Liu, Yang; Deng, Yong-Qiang; Jiang, Tao; Cheng, Gong; Zhang, Fu-Chun; Davidson, Andrew D; Song, Ya-Jun; Shi, Pei-Yong; Qin, Cheng-Feng

2018-02-14

The global spread of Zika virus (ZIKV) and its unexpected association with congenital defects necessitates the rapid development of a safe and effective vaccine. Here we report the development and characterization of a recombinant chimeric ZIKV vaccine candidate (termed ChinZIKV) that expresses the prM-E proteins of ZIKV using the licensed Japanese encephalitis live-attenuated vaccine SA14-14-2 as the genetic backbone. ChinZIKV retains its replication activity and genetic stability in vitro, while exhibiting an attenuation phenotype in multiple animal models. Remarkably, immunization of mice and rhesus macaques with a single dose of ChinZIKV elicits robust and long-lasting immune responses, and confers complete protection against ZIKV challenge. Significantly, female mice immunized with ChinZIKV are protected against placental and fetal damage upon ZIKV challenge during pregnancy. Overall, our study provides an alternative vaccine platform in response to the ZIKV emergency, and the safety, immunogenicity, and protection profiles of ChinZIKV warrant further clinical development.

Development of the PANVAC-VF vaccine for pancreatic cancer.

Science.gov (United States)

Petrulio, Christian A; Kaufman, Howard L

2006-02-01

PANVAC-VF is a vaccine regimen composed of a priming dose of recombinant vaccinia virus and booster doses of recombinant fowlpox virus expressing carcinoembryonic antigen, mucin-1 and a triad of costimulatory molecules (TRICOM), which include B7.1, intercellular adhesion molecule-1 and leukocyte function-associated antigen-3. Vaccination is administered by subcutaneous injection followed by 4 days of local recombinant adjuvant granulocyte-macrophage colony-stimulating factor at the vaccination site. The vaccine has been developed for patients with advanced pancreatic cancer and has now entered a randomized Phase III clinical trial. This review will describe the background of recombinant poxvirus technology for tumor vaccine development, detail the key preclinical studies supporting the regimen, review the clinical trials supporting the current Phase III study, and highlight the key challenges and future obstacles to successful implementation of PANVAC-VF for pancreatic cancer.

Design of clinical trials for therapeutic cancer vaccines development.

Science.gov (United States)

Mackiewicz, Jacek; Mackiewicz, Andrzej

2009-12-25

Advances in molecular and cellular biology as well as biotechnology led to definition of a group of drugs referred to as medicinal products of advanced technologies. It includes gene therapy products, somatic cell therapeutics and tissue engineering. Therapeutic cancer vaccines including whole cell tumor cells vaccines or gene modified whole cells belong to somatic therapeutics and/or gene therapy products category. The drug development is a multistep complex process. It comprises of two phases: preclinical and clinical. Guidelines on preclinical testing of cell based immunotherapy medicinal products have been defined by regulatory agencies and are available. However, clinical testing of therapeutic cancer vaccines is still under debate. It presents a serious problem since recently clinical efficacy of the number of cancer vaccines has been demonstrated that focused a lot of public attention. In general clinical testing in the current form is very expensive, time consuming and poorly designed what may lead to overlooking of products clinically beneficial for patients. Accordingly regulatory authorities and researches including Cancer Vaccine Clinical Trial Working Group proposed three regulatory solutions to facilitate clinical development of cancer vaccines: cost-recovery program, conditional marketing authorization, and a new development paradigm. Paradigm includes a model in which cancer vaccines are investigated in two types of clinical trials: proof-of-principle and efficacy. The proof-of-principle trial objectives are: safety; dose selection and schedule of vaccination; and demonstration of proof-of-principle. Efficacy trials are randomized clinical trials with objectives of demonstrating clinical benefit either directly or through a surrogate. The clinical end points are still under debate.

Meningococcal Vaccine (For Parents)

Science.gov (United States)

... previous dose of meningococcal vaccine, to the DTaP vaccine , or to latex If your child has a history of Guillain-Barré syndrome (a disease of the nervous system that causes progressive weakness), talk to your doctor about whether the vaccines are a good idea. Caring for Your Child ...

Efforts Towards The Development Of Recombinant Vaccines Against

African Journals Online (AJOL)

ABSTRACT. Hemorrhagic septicemia is caused by gram-negative bacterium of Pasteurella multocida (P. multocida) strains. Most of the current vaccines against P. multocida have shortcomings. Presently, there is increasing efforts towards construction of recombinant clone for vaccine development against P. multocida.

Development of a Subunit Vaccine for Contagious Bovine ...

International Development Research Centre (IDRC) Digital Library (Canada)

Their work has set the stage for commercial development of a sub-unit vaccine. ... The sub-unit vaccine will be cost-effective, easy to produce, and safe. How it will make a ... IDRC invites applications for the IDRC Doctoral Research Awards.

Development of replication-deficient adenovirus malaria vaccines.

Science.gov (United States)

Hollingdale, Michael R; Sedegah, Martha; Limbach, Keith

2017-03-01

Malaria remains a major threat to endemic populations and travelers, including military personnel to these areas. A malaria vaccine is feasible, as radiation attenuated sporozoites induce nearly 100% efficacy. Areas covered: This review covers current malaria clinical trials using adenoviruses and pre-clinical research. Heterologous prime-boost regimens, including replication-deficient human adenovirus 5 (HuAd5) carrying malaria antigens, are efficacious. However, efficacy appears to be adversely affected by pre-existing anti-HuAd5 antibodies. Current strategies focus on replacing HuAd5 with rarer human adenoviruses or adenoviruses isolated from non-human primates (NHPs). The chimpanzee adenovirus ChAd63 is undergoing evaluation in clinical trials including infants in malaria-endemic areas. Key antigens have been identified and are being used alone, in combination, or with protein subunit vaccines. Gorilla adenoviruses carrying malaria antigens are also currently being evaluated in preclinical models. These replacement adenovirus vectors will be successfully used to develop vaccines against malaria, as well as other infectious diseases. Expert commentary: Simplified prime-boost single shot regimens, dry-coated live vector vaccines or silicon microneedle arrays could be developed for malaria or other vaccines. Replacement vectors with similar or superior immunogenicity have rapidly advanced, and several are now in extensive Phase 2 and beyond in malaria as well as other diseases, notably Ebola.

Novel Platforms for the Development of a Universal influenza vaccine

DEFF Research Database (Denmark)

Kumar, Arun; Meldgaard, Trine Sundebo; Bertholet, Sylvie

2018-01-01

Despite advancements in immunotherapeutic approaches, influenza continues to cause severe illness, particularly among immunocompromised individuals, young children, and elderly adults. Vaccination is the most effective way to reduce rates of morbidity and mortality caused by influenza viruses....... Frequent genetic shift and drift among influenzavirus strains with the resultant disparity between circulating and vaccine virus strains limits the effectiveness of the available conventional influenza vaccines. One approach to overcome this limitation is to develop a universal influenza vaccine that could...... provide protection against all subtypes of influenza viruses. Moreover, the development of a novel or improved universal influenza vaccines may be greatly facilitated by new technologies including virus-like particles, T-cell-inducing peptides and recombinant proteins, synthetic viruses, broadly...

A national multicenter phase 2 study of prostate-specific antigen (PSA) pox virus vaccine with sequential androgen ablation therapy in patients with PSA progression: ECOG 9802.

Science.gov (United States)

DiPaola, Robert S; Chen, Yu-Hui; Bubley, Glenn J; Stein, Mark N; Hahn, Noah M; Carducci, Michael A; Lattime, Edmund C; Gulley, James L; Arlen, Philip M; Butterfield, Lisa H; Wilding, George

2015-09-01

E9802 was a phase 2 multi-institution study conducted to evaluate the safety and effectiveness of vaccinia and fowlpox prostate-specific antigen (PSA) vaccine (step 1) followed by combination with androgen ablation therapy (step 2) in patients with PSA progression without visible metastasis. To test the hypothesis that vaccine therapy in this early disease setting will be safe and have a biochemical effect that would support future studies of immunotherapy in patients with minimal disease burden. Patients who had PSA progression following local therapy were treated with PROSTVAC-V (vaccinia)/TRICOM on cycle 1 followed by PROSTVAC-F (fowlpox)/TRICOM for subsequent cycles in combination with granulocyte-macrophage colony-stimulating factor (step 1). Androgen ablation was added on progression (step 2). Step 1 primary end points included progression at 6 mo and characterization of change in PSA velocity pretreatment to post-treatment. Step 2 end points included PSA response with combined vaccine and androgen ablation. In step 1, 25 of 40 eligible patients (63%) were progression free at 6 mo after registration (90% confidence interval [CI], 48-75). The median pretreatment PSA velocity was 0.13 log(PSA)/mo, in contrast to median postregistration velocity of 0.09 log(PSA)/mo (p=0.02), which is an increase in median PSA doubling time from 5.3 mo to 7.7 mo. No grade ≥4 treatment-related toxicity was observed. In the 27 patients eligible and treated for step 2, 20 patients achieved a complete response (CR) at 7 mo (CR rate: 74%; 90% CI, 57-87). Although supportive of larger studies in the cooperative group setting, this study is limited by the small number of patients and the absence of a control group as in a phase 3 study. A viral PSA vaccine can be administered safely in the multi-institutional cooperative group setting to patients with minimal disease volume alone and combined with androgen ablation, supporting the feasibility of future phase 3 studies in this

Strategies to advance vaccine technologies for resource-poor settings.

Science.gov (United States)

Kristensen, Debra; Chen, Dexiang

2013-04-18

New vaccine platform and delivery technologies that can have significant positive impacts on the effectiveness, acceptability, and safety of immunizations in developing countries are increasingly available. Although donor support for vaccine technology development is strong, the uptake of proven technologies by the vaccine industry and demand for them by purchasers continues to lag. This article explains the challenges and opportunities associated with accelerating the availability of innovative and beneficial vaccine technologies to meet critical needs in resource-poor settings over the next decade. Progress will require increased dialog between the public and private sectors around vaccine product attributes; establishment of specifications for vaccines that mirror programmatic needs; stronger encouragement of vaccine developers to consider novel technologies early in the product development process; broader facilitation of research and access to technologies through the formation of centers of excellence; the basing of vaccine purchase decisions on immunization systems costs rather than price per dose alone; possible subsidization of early technology adoption costs for vaccine producers that take on the risks of new technologies of importance to the public sector; and the provision of data to purchasers, better enabling them to make informed decisions that take into account the value of specific product attributes. Copyright © 2012 Elsevier Ltd. All rights reserved.

[Development of current smallpox vaccines].

Science.gov (United States)

Maksiutov, R A; Gavrilova, E V; Shchelkunov, S N

2011-01-01

The review gives data on the history of smallpox vaccination and shows the high topicality of designing the current safe vaccines against orthopoxviruses. Four generations of live smallpox, protein subunit, and DNA vaccines are considered. Analysis of the data published leads to the conclusion that it is promising to use the up-to-date generations of safe smallpox subunit or DNA vaccines for mass primary immunization with possible further revaccination with classical live vaccine.

Efforts to monitor Global progress on individual and community demand for immunization: Development of definitions and indicators for the Global Vaccine Action Plan Strategic Objective 2.

Science.gov (United States)

Hickler, Benjamin; MacDonald, Noni E; Senouci, Kamel; Schuh, Holly B

2017-06-16

The Second Strategic Objective of the Global Vaccine Action Plan, "individuals and communities understand the value of vaccines and demand immunization as both their right and responsibility", differs from the other five in that it does not focus on supply-side aspects of immunization programs but rather on public demand for vaccines and immunization services. This commentary summarizes the work (literature review, consultations with experts, and with potential users) and findings of the UNICEF/World Health Organization Strategic Objective 2 informal Working Group on Vaccine Demand, which developed a definition for demand and indicators related to Strategic Objective 2. Demand for vaccines and vaccination is a complex concept that is not external to supply systems but rather encompasses the interaction between human behaviors and system structure and dynamics. Copyright © 2017. Published by Elsevier Ltd.

Efforts towards the development of recombinant Vaccines against ...

African Journals Online (AJOL)

Hemorrhagic septicemia is caused by gram-negative bacterium of Pasteurella multocida (P. multocida) strains. Most of the current vaccines against P. multocida have shortcomings. Presently, there is increasing efforts towards construction of recombinant clone for vaccine development against P. multocida. In this review an ...

Ebola hemorrhagic Fever and the current state of vaccine development.

Science.gov (United States)

Hong, Joo Eun; Hong, Kee-Jong; Choi, Woo Young; Lee, Won-Ja; Choi, Yeon Hwa; Jeong, Chung-Hyeon; Cho, Kwang-Il

2014-12-01

Current Ebola virus outbreak in West Africa already reached the total number of 1,323 including 729 deaths by July 31st. the fatality is around 55% in the southeastern area of Guinea, Sierra Leone, Liberia, and Nigeria. The number of patients with Ebola Hemorrhagic Fever (EHF) was continuously increasing even though the any effective therapeutics or vaccines has not been developed yet. The Ebola virus in Guinea showed 98% homology with Zaire Ebola Virus. Study of the pathogenesis of Ebola virus infection and assess of the various candidates of vaccine have been tried for a long time, especially in United States and some European countries. Even though the attenuated live vaccine and DNA vaccine containing Ebola viral genes were tested and showed efficacy in chimpanzees, those candidates still need clinical tests requiring much longer time than the preclinical development to be approved for the practical treatment. It can be expected to eradicate Ebola virus by a safe and efficient vaccine development similar to the case of smallpox virus which was extinguished from the world by the variola vaccine.

Development of a thermostable microneedle patch for influenza vaccination

Science.gov (United States)

Mistilis, Matthew; Bommarius, Andreas S; Prausnitz, Mark R.

2017-01-01

The goal of this study is to develop thermostable microneedle patch formulations for influenza vaccine that can be partially or completely removed from the cold chain. During vaccine drying associated with microneedle patch manufacturing, ammonium acetate and HEPES buffer salts stabilized influenza vaccine, surfactants had little effect during drying, drying temperature had weak effects on vaccine stability, and drying on polydimethylsiloxane led to increased stability compared to drying on stainless steel. A number of excipients, mostly polysaccharides and some amino acids, further stabilized the influenza vaccine during drying. Over longer time scales of storage, combinations of stabilizers preserved the most vaccine activity. Finally, dissolving microneedle patches formulated with arginine and calcium heptagluconate had no significant activity loss for all three strains of seasonal influenza vaccine during storage at room temperature for six months. We conclude that appropriately formulated microneedle patches can exhibit remarkable thermostability that could enable storage and distribution of influenza vaccine outside the cold chain. PMID:25448542

Advances in neglected tropical disease vaccines: Developing relative potency and functional assays for the Na-GST-1/Alhydrogel hookworm vaccine.

Directory of Open Access Journals (Sweden)

Jill B Brelsford

2017-02-01

Full Text Available A new generation of vaccines for the neglected tropical diseases (NTDs have now advanced into clinical development, with the Na-GST-1/Alhydrogel Hookworm Vaccine already being tested in Phase 1 studies in healthy adults. The current manuscript focuses on the often overlooked critical aspects of NTD vaccine product development, more specifically, vaccine stability testing programs. A key measure of vaccine stability testing is "relative potency" or the immunogenicity of the vaccine during storage. As with most NTD vaccines, the Na-GST-1/Alhydrogel Hookworm Vaccine was not developed by attenuation or inactivation of the pathogen (Necator americanus, so conventional methods for measuring relative potency are not relevant for this investigational product. Herein, we describe a novel relative potency testing program and report for the first time on the clinical lot of this NTD vaccine during its first 60 months of storage at 2-8°C. We also describe the development of a complementary functional assay that measures the ability of IgG from animals or humans immunized with Na-GST-1/Alhydrogel to neutralize this important hookworm enzyme. While 90% inhibition of the catalytic activity of Na-GST-1 was achieved in animals immunized with Na-GST-1/Alhydrogel, lower levels of inhibition were observed in immunized humans. Moreover, anti-Na-GST-1 antibodies from volunteers in non-hookworm endemic areas were better able to inhibit catalytic activity than anti-Na-GST-1 antibodies from volunteers resident in hookworm endemic areas. The results described herein provide the critical tools for the product development of NTD vaccines.

Advances in neglected tropical disease vaccines: Developing relative potency and functional assays for the Na-GST-1/Alhydrogel hookworm vaccine

Science.gov (United States)

Brelsford, Jill B.; Plieskatt, Jordan L.; Yakovleva, Anna; Jariwala, Amar; Keegan, Brian P.; Peng, Jin; Xia, Pengjun; Li, Guangzhao; Campbell, Doreen; Periago, Maria Victoria; Correa-Oliveira, Rodrigo; Bottazzi, Maria Elena; Hotez, Peter J.

2017-01-01

A new generation of vaccines for the neglected tropical diseases (NTDs) have now advanced into clinical development, with the Na-GST-1/Alhydrogel Hookworm Vaccine already being tested in Phase 1 studies in healthy adults. The current manuscript focuses on the often overlooked critical aspects of NTD vaccine product development, more specifically, vaccine stability testing programs. A key measure of vaccine stability testing is "relative potency" or the immunogenicity of the vaccine during storage. As with most NTD vaccines, the Na-GST-1/Alhydrogel Hookworm Vaccine was not developed by attenuation or inactivation of the pathogen (Necator americanus), so conventional methods for measuring relative potency are not relevant for this investigational product. Herein, we describe a novel relative potency testing program and report for the first time on the clinical lot of this NTD vaccine during its first 60 months of storage at 2–8°C. We also describe the development of a complementary functional assay that measures the ability of IgG from animals or humans immunized with Na-GST-1/Alhydrogel to neutralize this important hookworm enzyme. While 90% inhibition of the catalytic activity of Na-GST-1 was achieved in animals immunized with Na-GST-1/Alhydrogel, lower levels of inhibition were observed in immunized humans. Moreover, anti-Na-GST-1 antibodies from volunteers in non-hookworm endemic areas were better able to inhibit catalytic activity than anti-Na-GST-1 antibodies from volunteers resident in hookworm endemic areas. The results described herein provide the critical tools for the product development of NTD vaccines. PMID:28192438

Update on the Clinical Development of Candidate Malaria Vaccines

National Research Council Canada - National Science Library

Ballou, W. R; Arevalo-Herrera, Myriam; Carucci, Daniel; Richie, Thomas L; Corradin, Giampietro; Diggs, Carter; Druilhe, Pierre; Giersing, Birgitte K; Saul, Allan; Heppner, D. G

2004-01-01

... powerful driver for stimulating clinical development of candidate vaccines for malaria. This new way forward promises to greatly increase the likelihood of bringing a safe and effective vaccine to licensure...

[Overview of the Ebola vaccines in pre-clinical and clinical development].

Science.gov (United States)

Buchy, P

2016-10-01

The Ebola epidemic that occurred in West Africa between 2013-2016 significantly accelerated the research and development of Ebola vaccines. Few dozens of clinical trials have been recently conducted leading to opportunities to test several new vaccine candidates. Other vaccines are still in early development phases (table 1). This paper provides an overview of the new developments in that area.

Methods and Protocols for Developing Prion Vaccines.

Science.gov (United States)

Marciniuk, Kristen; Taschuk, Ryan; Napper, Scott

2016-01-01

Prion diseases denote a distinct form of infectivity that is based in the misfolding of a self-protein (PrP(C)) into a pathological, infectious conformation (PrP(Sc)). Efforts to develop vaccines for prion diseases have been complicated by the potential dangers that are associated with induction of immune responses against a self-protein. As a consequence, there is considerable appeal for vaccines that specifically target the misfolded prion conformation. Such conformation-specific immunotherapy is made possible through the identification of vaccine targets (epitopes) that are exclusively presented as a consequence of misfolding. An immune response directed against these targets, termed disease-specific epitopes (DSEs), has the potential to spare the function of the native form of the protein while clearing, or neutralizing, the infectious isomer. Although identification of DSEs represents a critical first step in the induction of conformation-specific immune responses, substantial efforts are required to translate these targets into functional vaccines. Due to the poor immunogenicity that is inherent to self-proteins, and that is often associated with short peptides, substantial efforts are required to overcome tolerance-to-self and maximize the resultant immune response following DSE-based immunization. This often includes optimization of target sequences in terms of immunogenicity and development of effective formulation and delivery strategies for the associated peptides. Further, these vaccines must satisfy additional criteria from perspectives of specificity (PrP(C) vs. PrP(Sc)) and safety (antibody-induced template-driven misfolding of PrP(C)). The emphasis of this report is on the steps required to translate DSEs into prion vaccines and subsequent evaluation of the resulting immune responses.

Self-amplifying mRNA vaccines.

Science.gov (United States)

Brito, Luis A; Kommareddy, Sushma; Maione, Domenico; Uematsu, Yasushi; Giovani, Cinzia; Berlanda Scorza, Francesco; Otten, Gillis R; Yu, Dong; Mandl, Christian W; Mason, Peter W; Dormitzer, Philip R; Ulmer, Jeffrey B; Geall, Andrew J

2015-01-01

This chapter provides a brief introduction to nucleic acid-based vaccines and recent research in developing self-amplifying mRNA vaccines. These vaccines promise the flexibility of plasmid DNA vaccines with enhanced immunogenicity and safety. The key to realizing the full potential of these vaccines is efficient delivery of nucleic acid to the cytoplasm of a cell, where it can amplify and express the encoded antigenic protein. The hydrophilicity and strong net negative charge of RNA impedes cellular uptake. To overcome this limitation, electrostatic complexation with cationic lipids or polymers and physical delivery using electroporation or ballistic particles to improve cellular uptake has been evaluated. This chapter highlights the rapid progress made in using nonviral delivery systems for RNA-based vaccines. Initial preclinical testing of self-amplifying mRNA vaccines has shown nonviral delivery to be capable of producing potent and robust innate and adaptive immune responses in small animals and nonhuman primates. Historically, the prospect of developing mRNA vaccines was uncertain due to concerns of mRNA instability and the feasibility of large-scale manufacturing. Today, these issues are no longer perceived as barriers in the widespread implementation of the technology. Currently, nonamplifying mRNA vaccines are under investigation in human clinical trials and can be produced at a sufficient quantity and quality to meet regulatory requirements. If the encouraging preclinical data with self-amplifying mRNA vaccines are matched by equivalently positive immunogenicity, potency, and tolerability in human trials, this platform could establish nucleic acid vaccines as a versatile new tool for human immunization. Copyright © 2015 Elsevier Inc. All rights reserved.

Current state and challenges in developing oral vaccines.

Science.gov (United States)

Vela Ramirez, Julia E; Sharpe, Lindsey A; Peppas, Nicholas A

2017-05-15

While vaccination remains the most cost effective strategy for disease prevention, communicable diseases persist as the second leading cause of death worldwide. There is a need to design safe, novel vaccine delivery methods to protect against unaddressed and emerging diseases. Development of vaccines administered orally is preferable to traditional injection-based formulations for numerous reasons including improved safety and compliance, and easier manufacturing and administration. Additionally, the oral route enables stimulation of humoral and cellular immune responses at both systemic and mucosal sites to establish broader and long-lasting protection. However, oral delivery is challenging, requiring formulations to overcome the harsh gastrointestinal (GI) environment and avoid tolerance induction to achieve effective protection. Here we address the rationale for oral vaccines, including key biological and physicochemical considerations for next-generation oral vaccine design. Copyright © 2017 Elsevier B.V. All rights reserved.

Challenges in the research and development of new human vaccines

Directory of Open Access Journals (Sweden)

T. Barbosa

2013-02-01

Full Text Available The field of vaccinology was born from the observations by the fathers of vaccination, Edward Jenner and Louis Pasteur, that a permanent, positive change in the way our bodies respond to life-threatening infectious diseases can be obtained by specific challenge with the inactivated infectious agent performed in a controlled manner, avoiding the development of clinical disease upon exposure to the virulent pathogen. Many of the vaccines still in use today were developed on an empirical basis, essentially following the paradigm established by Pasteur, “isolate, inactivate, and inject” the disease-causing microorganism, and are capable of eliciting uniform, long-term immune memory responses that constitute the key to their proven efficacy. However, vaccines for pathogens considered as priority targets of public health concern are still lacking. The literature tends to focus more often on vaccine research problems associated with specific pathogens, but it is increasingly clear that there are common bottlenecks in vaccine research, which need to be solved in order to advance the development of the field as a whole. As part of a group of articles, the objective of the present report is to pinpoint these bottlenecks, exploring the literature for common problems and solutions in vaccine research applied to different situations. Our goal is to stimulate brainstorming among specialists of different fields related to vaccine research and development. Here, we briefly summarize the topics we intend to deal with in this discussion.

Dengue human infection models to advance dengue vaccine development.

Science.gov (United States)

Larsen, Christian P; Whitehead, Stephen S; Durbin, Anna P

2015-12-10

Dengue viruses (DENV) currently infect approximately 400 million people each year causing millions to seek care and overwhelming the health care infrastructure in endemic areas. Vaccines to prevent dengue and therapeutics to treat dengue are not currently available. The efficacy of the most advanced candidate vaccine against symptomatic dengue in general and DENV-2 in particular was much lower than expected, despite the ability of the vaccine to induce neutralizing antibody against all four DENV serotypes. Because seroconversion to the DENV serotypes following vaccination was thought to be indicative of induced protection, these results have made it more difficult to assess which candidate vaccines should or should not be evaluated in large studies in endemic areas. A dengue human infection model (DHIM) could be extremely valuable to down-select candidate vaccines or therapeutics prior to engaging in efficacy trials in endemic areas. Two DHIM have been developed to assess the efficacy of live attenuated tetravalent (LATV) dengue vaccines. The first model, developed by the Laboratory of Infectious Diseases at the U. S. National Institutes of Health, utilizes a modified DENV-2 strain DEN2Δ30. This virus was derived from the DENV-2 Tonga/74 that caused only very mild clinical infection during the outbreak from which it was recovered. DEN2Δ30 induced viremia in 100%, rash in 80%, and neutropenia in 27% of the 30 subjects to whom it was given. The Walter Reed Army Institute of Research (WRAIR) is developing a DHIM the goal of which is to identify DENV that cause symptomatic dengue fever. WRAIR has evaluated seven viruses and has identified two that meet dengue fever criteria. Both of these models may be very useful in the evaluation and down-selection of candidate dengue vaccines and therapeutics. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Development of inactivated-local isolate vaccine for infectious bronchitis

Directory of Open Access Journals (Sweden)

Darminto

1999-06-01

Full Text Available Infectious bronchitis (IB is an acute highly contagious viral respiratory disease of poultry caused by coronavirus. The disease causes high mortality in young chicks, reduce body weight gain in broilers and remarkable drop in egg production. IB can only be controlled by vaccination, but due to the antigenic variation among serotypes of IB viruses, the effective IB vaccine should be prepared from local isolates. The aim of this research is to develop inactivated IB vaccine derived from local IB isolates. Local isolates of IB viruses designated as I-37, I-269 and PTS-III were propagated respectively in specific pathogen free (SPF chicken eggs, the viruses then were inactivated by formaline at final concentration of 1:1,000. Subsequently, the inactivated viruses were mixed and emulsified in oil emulsion adjuvant with sorbitant mono-oleic as an emulsifier. The vaccine then was tested for its safety, potency and efficacy in broiler chickens. Birds inoculated twice with a two-week interval by inactivated vaccine did not show any adverse reaction, either systemic or local reaction. The inoculated birds developed antibody responses with high titre, while antibody of the control birds remain negative. In addition, efficacy test which was conducted in broilers demonstrated that birds vaccinated by live-commercial vaccine and boosted three weeks later by Balitvet inactivated vaccine showed high level of antibody production which provided high level of protection against challenged virus (76% against I-37, 92% against I-269 and 68% against PTS-III challenge viruses. From this study, it can be concluded that inactivated local IB vaccine is considered to be safe, potent and efficacious. The vaccine stimulates high titre of antibody responses, which provide high level of protection against challenged viruses.

Update on the current status of cytomegalovirus vaccines.

Science.gov (United States)

Sung, Heungsup; Schleiss, Mark R

2010-11-01

Human cytomegalovirus (HCMV) is ubiquitous in all populations, and is the most commonly recognized cause of congenital viral infection in developed countries. On the basis of the economic costs saved and the improvement in quality of life that could potentially be conferred by a successful vaccine for prevention of congenital HCMV infection, the Institute of Medicine has identified HCMV vaccine development as a major public health priority. An effective vaccine could potentially also be beneficial in preventing or ameliorating HCMV disease in immunocompromised individuals. Although there are no licensed HCMV vaccines currently available, enormous progress has been made in the last decade, as evidenced by the recently reported results of a Phase II trial of a glycoprotein B vaccine for the prevention of HCMV infection in seronegative women of childbearing age. HCMV vaccines currently in clinical trials include: glycoprotein B subunit vaccines; alphavirus replicon particle vaccines; DNA vaccines; and live-attenuated vaccines. A variety of vaccine strategies are also being examined in preclinical systems and animal models of infection. These include: recombinant vesicular stomatitis virus vaccines; recombinant modified vaccinia virus Ankara; replication-deficient adenovirus-vectored vaccines; and recombinant live-attenuated virus vaccines generated by mutagenesis of cloned rodent CMV genomes maintained as bacterial artificial chromosomes in Escherichia coli. In this article, we provide an overview of the current state of clinical trials and preclinical development of vaccines against HCMV, with an emphasis on studies that have been conducted in the past 5 years. We also summarize a number of recent advances in the study of the biology of HCMV, particularly with respect to epithelial and endothelial cell entry of the virus, which have implications for future vaccine design.

Recent advances in the molecular design of synthetic vaccines

Science.gov (United States)

Jones, Lyn H.

2015-12-01

Vaccines have typically been prepared using whole organisms. These are normally either attenuated bacteria or viruses that are live but have been altered to reduce their virulence, or pathogens that have been inactivated and effectively killed through exposure to heat or formaldehyde. However, using whole organisms to elicit an immune response introduces the potential for infections arising from a reversion to a virulent form in live pathogens, unproductive reactions to vaccine components or batch-to-batch variability. Synthetic vaccines, in which a molecular antigen is conjugated to a carrier protein, offer the opportunity to circumvent these problems. This Perspective will highlight the progress that has been achieved in developing synthetic vaccines using a variety of molecular antigens. In particular, the different approaches used to develop conjugate vaccines using peptide/proteins, carbohydrates and other small molecule haptens as antigens are compared.

Clinical development of placental malaria vaccines and immunoassays harmonization

DEFF Research Database (Denmark)

Chêne, Arnaud; Houard, Sophie; Nielsen, Morten A

2016-01-01

Placental malaria caused by Plasmodium falciparum infection constitutes a major health problem manifesting as severe disease and anaemia in the mother, impaired fetal development, low birth weight or spontaneous abortion. Prevention of placental malaria currently relies on two key strategies...... that are losing efficacy due to spread of resistance: long-lasting insecticide-treated nets and intermittent preventive treatment during pregnancy. A placental malaria vaccine would be an attractive, cost-effective complement to the existing control tools. Two placental malaria vaccine candidates are currently...... in Phase Ia/b clinical trials. During two workshops hosted by the European Vaccine Initiative, one in Paris in April 2014 and the other in Brussels in November 2014, the main actors in placental malaria vaccine research discussed the harmonization of clinical development plans and of the immunoassays...

Heterogeneity of Rotavirus Vaccine Efficacy Among Infants in Developing Countries.

Science.gov (United States)

Gruber, Joann F; Hille, Darcy A; Liu, G Frank; Kaplan, Susan S; Nelson, Micki; Goveia, Michelle G; Mast, T Christopher

2017-01-01

Rotavirus is the leading cause of severe diarrhea worldwide in young children. Although rotavirus vaccine efficacy is high in developed countries, efficacy is lower in developing countries. Here, we investigated heterogeneity of rotavirus vaccine efficacy by infant characteristics in developing countries. An exploratory, post hoc analysis was conducted using randomized controlled trial data of the pentavalent rotavirus vaccine (RV5) conducted in Africa and Asia (NCT00362648). Infants received either 3 doses of vaccine/placebo and were followed for up to 2 years. Within subgroups, vaccine efficacies and 95% confidence intervals (CIs) against rotavirus gastroenteritis (RVGE) were estimated using Poisson regression. We assessed heterogeneity of efficacy by age at first dose, gender, breastfeeding status and nutrition status. African children receiving the first dose at efficacy (23.7%; 95% CI: -8.2%-46.3%) than those vaccinated at ≥8 weeks (59.1%; 95% CI: 34.0%-74.6%). Marginally statistically significant differences were observed by age at first dose, gender and underweight status in Ghana and gender in Asian countries. Heterogeneity of efficacy was observed for age at first dose in African countries. This was an exploratory analysis; additional studies are needed to validate these results.

Considerations for sustainable influenza vaccine production in developing countries.

Science.gov (United States)

Nannei, Claudia; Chadwick, Christopher; Fatima, Hiba; Goldin, Shoshanna; Grubo, Myriam; Ganim, Alexandra

2016-10-26

Through its Global Action Plan for Influenza Vaccines (GAP), the World Health Organization (WHO) in collaboration with the United States Department of Health and Human Services has produced a checklist to support policy-makers and influenza vaccine manufacturers in identifying key technological, political, financial, and logistical issues affecting the sustainability of influenza vaccine production. This checklist highlights actions in five key areas that are beneficial for establishing successful local vaccine manufacturing. These five areas comprise: (1) the policy environment and health-care systems; (2) surveillance systems and influenza evidence; (3) product development and manufacturing; (4) product approval and regulation; and (5) communication to support influenza vaccination. Incorporating the checklist into national vaccine production programmes has identified the policy gaps and next steps for countries involved in GAP's Technology Transfer Initiative. Lessons learnt from country experiences provide context and insight that complement the checklist's goal of simplifying the complexities of influenza prevention, preparedness, and vaccine manufacturing. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

The impact of globalization on vaccine development and availability.

Science.gov (United States)

Milstien, Julie B; Kaddar, Miloud; Kieny, Marie Paule

2006-01-01

Globalization is likely to affect many aspects of public health, one of which is vaccine-preventable communicable diseases. Important forces include increased funding initiatives supporting immunization at the global level; regulatory harmonization; widespread intellectual property rights provisions through the World Trade Organization agreements; the emergence of developing-country manufacturers as major players in vaccine supply; and the appearance of new communicable disease threats, including those potentially linked to bioterrorism. All of these forces can affect, either positively and negatively, the development and availability of vaccines. Harnessing these will be a challenge for policymakers and immunization stakeholders.

Developing whole mycobacteria cell vaccines for tuberculosis: Workshop proceedings, Max Planck Institute for Infection Biology, Berlin, Germany, July 9, 2014.

Science.gov (United States)

2015-06-12

On July 9, 2014, Aeras and the Max Planck Institute for Infection Biology convened a workshop entitled "Whole Mycobacteria Cell Vaccines for Tuberculosis" at the Max Planck Institute for Infection Biology on the grounds of the Charité Hospital in Berlin, Germany, close to the laboratory where, in 1882, Robert Koch first identified Mycobacterium tuberculosis (Mtb) as the pathogen responsible for tuberculosis (TB). The purpose of the meeting was to discuss progress in the development of TB vaccines based on whole mycobacteria cells. Live whole cell TB vaccines discussed at this meeting were derived from Mtb itself, from Bacille Calmette-Guérin (BCG), the only licensed vaccine against TB, which was genetically modified to reduce pathogenicity and increase immunogenicity, or from commensal non-tuberculous mycobacteria. Inactivated whole cell TB and non-tuberculous mycobacterial vaccines, intended as immunotherapy or as safer immunization alternatives for HIV+ individuals, also were discussed. Workshop participants agreed that TB vaccine development is significantly hampered by imperfect animal models, unknown immune correlates of protection and the absence of a human challenge model. Although a more effective TB vaccine is needed to replace or enhance the limited effectiveness of BCG in all age groups, members of the workshop concurred that an effective vaccine would have the greatest impact on TB control when administered to adolescents and adults, and that use of whole mycobacteria cells as TB vaccine candidates merits greater support, particularly given the limited understanding of the specific Mtb antigens necessary to generate an immune response capable of preventing Mtb infection and/or disease. Copyright © 2015. Published by Elsevier Ltd.. All rights reserved.

Prophylactic and Therapeutic Vaccination against Hepatitis C Virus (HCV: Developments and Future Perspectives

Directory of Open Access Journals (Sweden)

Marian E. Major

2009-08-01

Full Text Available Studies in patients and chimpanzees that spontaneously clear Hepatitis C Virus (HCV have demonstrated that natural immunity to the virus is induced during primary infections and that this immunity can be cross protective. These discoveries led to optimism regarding prophylactic HCV vaccines and a number of studies in the chimpanzee model have been performed, all of which resulted in modified infections after challenge but did not always prevent persistence of the virus. Therapeutic vaccine strategies have also been pursued in an effort to reduce the costs and side effects associated with anti-viral drug treatment. This review summarizes the studies performed thus far in both patients and chimpanzees for prophylactic and therapeutic vaccination, assesses the progress made and future perspectives.

Approaches and Perspectives for Development of African Swine Fever Virus Vaccines

Directory of Open Access Journals (Sweden)

Marisa Arias

2017-10-01

Full Text Available African swine fever (ASF is a complex disease of swine, caused by a large DNA virus belonging to the family Asfarviridae. The disease shows variable clinical signs, with high case fatality rates, up to 100%, in the acute forms. ASF is currently present in Africa and Europe where it circulates in different scenarios causing a high socio-economic impact. In most affected regions, control has not been effective in part due to lack of a vaccine. The availability of an effective and safe ASFV vaccines would support and enforce control–eradication strategies. Therefore, work leading to the rational development of protective ASF vaccines is a high priority. Several factors have hindered vaccine development, including the complexity of the ASF virus particle and the large number of proteins encoded by its genome. Many of these virus proteins inhibit the host’s immune system thus facilitating virus replication and persistence. We review previous work aimed at understanding ASFV–host interactions, including mechanisms of protective immunity, and approaches for vaccine development. These include live attenuated vaccines, and “subunit” vaccines, based on DNA, proteins, or virus vectors. In the shorter to medium term, live attenuated vaccines are the most promising and best positioned candidates. Gaps and future research directions are evaluated.

The Progress of Therapeutic Vaccination with Regard to Tuberculosis.

Science.gov (United States)

Cardona, Pere-Joan

2016-01-01

A major problem with tuberculosis (TB) control is the long duration of drug therapy-both for latent and for active TB. Therapeutic vaccination has been postulated to improve this situation, and to this end there are several candidates already in clinical phases of development. These candidates follow two main designs, namely bacilli-directed therapy based on inactivated -whole or -fragmented bacillus ( Mycobacterium w and RUTI) or fusion proteins that integrate non-replicating bacilli -related antigens (H56 vaccine), and host-directed therapy to reduce the tissue destruction. The administration of inactivated Mycobacterium vaccae prevents the "Koch phenomenon" response, and oral administration of heat-killed Mycobacterium manresensis prevents excessive neutrophilic infiltration of the lesions. This review also tries to explain the success of Mycobacterium tuberculosis by reviewing its evolution from infection to disease, and highlights the lack of a definitive understanding of the natural history of TB pathology and the need to improve our knowledge on TB immunology and pathogenesis.

Options for improving effectiveness of rotavirus vaccines in developing countries.

Science.gov (United States)

Tissera, Marion S; Cowley, Daniel; Bogdanovic-Sakran, Nada; Hutton, Melanie L; Lyras, Dena; Kirkwood, Carl D; Buttery, Jim P

2017-04-03

Rotavirus gastroenteritis is a leading global cause of mortality and morbidity in young children due to diarrhea and dehydration. Over 85% of deaths occur in developing countries. In industrialised countries, 2 live oral rotavirus vaccines licensed in 2006 quickly demonstrated high effectiveness, dramatically reducing severe rotavirus gastroenteritis admissions in many settings by more than 90%. In contrast, the same vaccines reduced severe rotavirus gastroenteritis by only 30-60% in developing countries, but have been proven life-saving. Bridging this "efficacy gap" offers the possibility to save many more lives of children under the age of 5. The reduced efficacy of rotavirus vaccines in developing settings may be related to differences in transmission dynamics, as well as host luminal, mucosal and immune factors. This review will examine strategies currently under study to target the issue of reduced efficacy and effectiveness of oral rotavirus vaccines in developing settings.

Health workers and vaccination coverage in developing countries: an econometric analysis.

Science.gov (United States)

Anand, Sudhir; Bärnighausen, Till

2007-04-14

Vaccine-preventable diseases cause more than 1 million deaths among children in developing countries every year. Although health workers are needed to do vaccinations, the role of human resources for health as a determinant of vaccination coverage at the population level has not been investigated. Our aim was to test whether health worker density was positively associated with childhood vaccination coverage in developing countries. We did cross-country multiple regression analyses with coverage of three vaccinations--measles-containing vaccine (MCV); diphtheria, tetanus, and pertussis (DTP3); and poliomyelitis (polio3)--as dependent variables. Aggregate health worker density was an independent variable in one set of regressions; doctor and nurse densities were used separately in another set. We controlled for national income per person, female adult literacy, and land area. Health worker density was significantly associated with coverage of all three vaccinations (MCV p=0.0024; DTP3 p=0.0004; polio3 p=0.0008). However, when the effects of doctors and nurses were assessed separately, we found that nurse density was significantly associated with coverage of all three vaccinations (MCV p=0.0097; DTP3 p=0.0083; polio3 p=0.0089), but doctor density was not (MCV p=0.7953; DTP3 p=0.7971; polio3 p=0.7885). Female adult literacy was positively associated, and land area negatively associated, with vaccination coverage. National income per person had no effect on coverage. A higher density of health workers (nurses) increases the availability of vaccination services over time and space, making it more likely that children will be vaccinated. After controlling for other determinants, the level of income does not contribute to improved immunisation coverage. Health workers can be a major constraining factor on vaccination coverage in developing countries.

[Animal experimentation in the discovery and production of veterinary vaccines].

Science.gov (United States)

Audonnet, J Ch; Lechenet, J; Verschuere, B

2007-08-01

Veterinary vaccine research, development and production facilities must aim to improve animal welfare, respond to public concerns and meet regulatory requirements, while at the same time fulfilling their objective of producing evermore effective and safer vaccines. The use of animal experimentation for the development of new veterinary vaccines is inevitable, as no in vitro model can predict a candidate vaccine's ability to induce protection in the target species. Against the backdrop of ethical and regulatory constraints, constant progress is being made in creating the best possible conditions for animal experimentation. Keeping up to date with the constant changes in the field of animal ethics requires a particular effort on the part of the pharmaceutical industry, which must make careful changes to product registration documentation in accordance with each new development.

[Introduction of vaccination against human papillomavirus in developing countries: update and perspectives].

Science.gov (United States)

Hessel, L

2009-08-01

Cervical cancer and other diseases related to human papillomavirus (HPV) represent a global public health problem. Safe and effective vaccines are now available and already used in many industrialized countries. Immunization offers the best hope for protecting the population against a disease that is the second most deadly cancer in the developing world and the first most deadly in Africa. The World Health Organization currently recommends introduction of HVP vaccination in developing countries. Widespread vaccination could be beneficial in numerous domains other than primary prevention of cervical cancer. Efforts to overcome the numerous obstacles and speed up implementation of HVP vaccination programs are now underway in many areas ranging from related scientific issues such as epidemiology and clinical research to administrative concerns such as healthcare economics, vaccination guidelines, public acceptation, program funding, and universal access. Vaccine manufacturers have committed themselves to working in partnership with national and international organizations to ensure access to HPV vaccine for all countries regardless of economic level, Although numerous issues must be resolved to optimize the use of HPV vaccines and ensure synergistic integration of vaccination, screening and treatment, current initiatives and efforts should allow introduction of HPV vaccination in developing countries in a not too distant future.

Chemistry, manufacturing and control (CMC) and clinical trial technical support for influenza vaccine manufacturers.

Science.gov (United States)

Wahid, Rahnuma; Holt, Renee; Hjorth, Richard; Berlanda Scorza, Francesco

2016-10-26

With the support of the Biomedical Advanced Research and Development Authority (BARDA) of the US Department of Health and Human Services, PATH has contributed to the World Health Organization's (WHO's) Global Action Plan for Influenza Vaccines (GAP) by providing technical and clinical assistance to several developing country vaccine manufacturers (DCVMs). GAP builds regionally based independent and sustainable influenza vaccine production capacity to mitigate the overall global shortage of influenza vaccines. The program also ensures adequate influenza vaccine manufacturing capacity in the event of an influenza pandemic. Since 2009, PATH has worked closely with two DCVMs in Vietnam: the Institute of Vaccines and Medical Biologicals (IVAC) and VABIOTECH. Beginning in 2013, PATH also began working with Torlak Institute in Serbia; Instituto Butantan in Brazil; Serum Institute of India Private Ltd. in India; and Changchun BCHT Biotechnology Co. (BCHT) in China. The DCVMs supported under the GAP program all had existing influenza vaccine manufacturing capability and required technical support from PATH to improve vaccine yield, process efficiency, and product formulation. PATH has provided customized technical support for the manufacturing process to each DCVM based on their respective requirements. Additionally, PATH, working with BARDA and WHO, supported several DCVMs in the clinical development of influenza vaccine candidates progressing toward national licensure or WHO prequalification. As a result of the activities outlined in this review, several companies were able to make excellent progress in developing state-of-the-art manufacturing processes and completing early phase clinical trials. Licensure trials are currently ongoing or planned for several DCVMs. Copyright © 2016 Elsevier Ltd. All rights reserved.

Advances in the development of vaccines for dengue fever

Directory of Open Access Journals (Sweden)

Simmons M

2012-05-01

Full Text Available Monika Simmons1, Nimfa Teneza-Mora1, Robert Putnak21Viral and Rickettsial Diseases Department, Naval Medical Research Center, 2Division of Viral Diseases, Walter Reed Army Institute of Research, Silver Spring, MD, USAAbstract: Dengue fever is caused by the mosquito-borne dengue virus (DENV serotypes 1–4, and is the most common arboviral infection of humans in subtropical and tropical regions of the world. There are currently no prophylaxis or treatment options in the form of vaccines or antivirals, leaving vector control the only method of prevention. A particular challenge with DENV is that a successful vaccine has to be effective against all four serotypes without predisposing for antibody-mediated enhanced disease. In this review, we discuss the current lead vaccine candidates in clinical trials, as well as some second-generation vaccine candidates undergoing preclinical evaluation. In addition, we discuss DENV epidemiology, clinical disease and strategies used for Flavivirus antivirals in the past, the development of new DENV therapeutics, and their potential usefulness for prophylaxis and treatment.Keywords: tetravalent dengue vaccine, live attenuated vaccine, purified inactivated vaccine, DNA vaccine, antibody-dependent enhancement, antivirals

Technology Resource, Distribution, and Development Characteristics of Global Influenza Virus Vaccine: A Patent Bibliometric Analysis

Science.gov (United States)

Liu, Long; Yan, Zhe; Tao, Lixin; Guo, Xiuhua; Luo, Yanxia; Yan, Aoshuang

2015-01-01

Influenza virus vaccine (IVV) is a promising research domain that is closely related to global health matters, which has been acknowledged not only by scientists and technology developers, but also by policy-makers. Meanwhile, patents encompass valuable technological information and reflect the latest technological inventions as well as the innovative capability of a nation. However, little research has examined this up-and-coming research field using patent bibliometric method. Thus, this paper (a) designs the technology classification system and search strategy for the identification of IVV; and (b) presents a longitudinal analysis of the global IVV development based on the European Patent Office (EPO) patents. Bibliometric analysis is used to rank countries, institutions, inventors and technology subfields contributing to IVV technical progress. The results show that the global trends of IVV are a multi-developing feature of variety but an uneven technical resource distribution. Although the synthetic peptide vaccine is a comparatively young field, it already demonstrates the powerful vitality and the enormous development space. With the worldwide competition increasing, all nations especially China should be looking to increase devotion, enhance capability and regard effectiveness of technological innovation. PMID:26372160

Technology Resource, Distribution, and Development Characteristics of Global Influenza Virus Vaccine: A Patent Bibliometric Analysis.

Science.gov (United States)

Chen, Ning; Liu, Yun; Cheng, Yijie; Liu, Long; Yan, Zhe; Tao, Lixin; Guo, Xiuhua; Luo, Yanxia; Yan, Aoshuang

2015-01-01

Influenza virus vaccine (IVV) is a promising research domain that is closely related to global health matters, which has been acknowledged not only by scientists and technology developers, but also by policy-makers. Meanwhile, patents encompass valuable technological information and reflect the latest technological inventions as well as the innovative capability of a nation. However, little research has examined this up-and-coming research field using patent bibliometric method. Thus, this paper (a) designs the technology classification system and search strategy for the identification of IVV; and (b) presents a longitudinal analysis of the global IVV development based on the European Patent Office (EPO) patents. Bibliometric analysis is used to rank countries, institutions, inventors and technology subfields contributing to IVV technical progress. The results show that the global trends of IVV are a multi-developing feature of variety but an uneven technical resource distribution. Although the synthetic peptide vaccine is a comparatively young field, it already demonstrates the powerful vitality and the enormous development space. With the worldwide competition increasing, all nations especially China should be looking to increase devotion, enhance capability and regard effectiveness of technological innovation.

Technology Resource, Distribution, and Development Characteristics of Global Influenza Virus Vaccine: A Patent Bibliometric Analysis.

Directory of Open Access Journals (Sweden)

Ning Chen

Full Text Available Influenza virus vaccine (IVV is a promising research domain that is closely related to global health matters, which has been acknowledged not only by scientists and technology developers, but also by policy-makers. Meanwhile, patents encompass valuable technological information and reflect the latest technological inventions as well as the innovative capability of a nation. However, little research has examined this up-and-coming research field using patent bibliometric method. Thus, this paper (a designs the technology classification system and search strategy for the identification of IVV; and (b presents a longitudinal analysis of the global IVV development based on the European Patent Office (EPO patents. Bibliometric analysis is used to rank countries, institutions, inventors and technology subfields contributing to IVV technical progress. The results show that the global trends of IVV are a multi-developing feature of variety but an uneven technical resource distribution. Although the synthetic peptide vaccine is a comparatively young field, it already demonstrates the powerful vitality and the enormous development space. With the worldwide competition increasing, all nations especially China should be looking to increase devotion, enhance capability and regard effectiveness of technological innovation.

Development of vaccines and their use in the prevention of fungal infections.

Science.gov (United States)

Dixon, D M; Casadevall, A; Klein, B; Mendoza, L; Travassos, L; Deepe, G S

1998-01-01

Vaccine approaches to infectious diseases are widely applied and appreciated. Disciplines such as bacteriology and virology have a rich history of successful vaccine development. The complexity of eukaryotic systems presents additional challenges to the development of vaccines against them. These challenges are being met in the fields of parasitology, and are being revisited for application in oncology. Vaccine opportunities exist in medical mycology. The National Institute of Allergy and Infectious Diseases has held a series of workshops in medical mycology where the need to develop vaccines for fungal diseases was noted and where important opportunities were discussed. Major advances in vaccinology and the technology of antigen preparation and delivery have increased feasibility and heightened interest. The recent epidemic of coccidioidomycosis in the American Southwest has demonstrated the need for developing a vaccine as an effective preventive measure for those living in and for those who subsequently move into regions with the endemic mycoses. The XIIth Congress of the International Society for Human and Animal Mycology included a symposium that summarized new vaccination strategies for selected fungi: Candida albicans, Coccidioides immitis, and Trichophyton verrucosum. The goal of the present summary is to provide representative examples of continuing efforts relating to vaccine development within the medical mycological community highlighting Blastomyces dermatidis, Cryptococcus neoformans, Histoplasma capsulatum, Paracoccidioides brasiliensis, and Pythiumn insidiosum.

Development of an epitope-based HIV-1 vaccine strategy from HIV-1 lipopeptide to dendritic-based vaccines.

Science.gov (United States)

Surenaud, Mathieu; Lacabaratz, Christine; Zurawski, Gérard; Lévy, Yves; Lelièvre, Jean-Daniel

2017-10-01

Development of a safe, effective and globally affordable Human Immunodeficiency Virus strain 1 (HIV-1) vaccine offers the best hope for future control of the HIV-1 pandemic. However, with the exception of the recent RV144 trial, which elicited a modest level of protection against infection, no vaccine candidate has shown efficacy in preventing HIV-1 infection or in controlling virus replication in humans. There is also a great need for a successful immunotherapeutic vaccine since combination antiretroviral therapy (cART) does not eliminate the reservoir of HIV-infected cells. But to date, no vaccine candidate has proven to significantly alter the natural history of an individual with HIV-1 infection. Areas covered: For over 25 years, the ANRS (France Recherche Nord&Sud Sida-HIV hépatites) has been committed to an original program combining basic science and clinical research developing an epitope-based vaccine strategy to induce a multiepitopic cellular response against HIV-1. This review describes the evolution of concepts, based on strategies using HIV-1 lipopeptides towards the use of dendritic cell (DC) manipulation. Expert commentary: Understanding the crucial role of DCs in immune responses allowed moving from the non-specific administration of HIV-1 sequences with lipopeptides to DC-based vaccines. These DC-targeting strategies should improve HIV-1 vaccine efficacy.

CURRENT DEVELOPMENT STRATEGIES FOR VACCINES AND THE ROLE OF REVERSE VACCINOLOGY

OpenAIRE

RAJU.S , UMA MAHESHWARA RAO.V

2013-01-01

The concept of vaccination has been around forcenturies .Vaccines constitutes cost-effective measures forpreventing disease. Advances in biotechnology and anunderstanding of the inductive and effector components ofimmune responses have ushered in a „golden age‟ ofvaccine development and implementation. Many licensedvaccines have one or more ideal characteristics, but nonemanifests them all. Of the generic vaccine technologies andvaccination strategies in different stages of development,some h...

Vaccines for preventing infection with Pseudomonas aeruginosa in cystic fibrosis

DEFF Research Database (Denmark)

Johansen, H.K.; Gøtzsche, Peter C.; Johansen, Helle Krogh

2008-01-01

BACKGROUND: Chronic pulmonary infection in cystic fibrosis results in progressive lung damage. Once colonisation of the lungs with Pseudomonas aeruginosa occurs, it is almost impossible to eradicate. Vaccines, aimed at reducing infection with Pseudomonas aeruginosa, have been developed. OBJECTIVES......: To assess the effectiveness of vaccination against Pseudomonas aeruginosa in cystic fibrosis. SEARCH STRATEGY: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register using the terms vaccines AND pseudomonas (last search May 2008) and PubMed using the terms vaccin* AND cystic...... fibrosis (last search May 2008). SELECTION CRITERIA: Randomised trials (published or unpublished) comparing Pseudomonas aeruginosa vaccines (oral, parenteral or intranasal) with control vaccines or no intervention in cystic fibrosis. DATA COLLECTION AND ANALYSIS: The authors independently selected trials...

Vaccines for preventing infection with Pseudomonas aeruginosa in cystic fibrosis

DEFF Research Database (Denmark)

Johansen, Helle Krogh; Gøtzsche, Peter C

2015-01-01

BACKGROUND: Chronic pulmonary infection in cystic fibrosis results in progressive lung damage. Once colonisation of the lungs with Pseudomonas aeruginosa occurs, it is almost impossible to eradicate. Vaccines, aimed at reducing infection with Pseudomonas aeruginosa, have been developed....... This is an update of a previously published review. OBJECTIVES: To assess the effectiveness of vaccination against Pseudomonas aeruginosa in cystic fibrosis. SEARCH METHODS: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register using the terms vaccines AND pseudomonas (last search 30...... March 2015). We previously searched PubMed using the terms vaccin* AND cystic fibrosis (last search 30 May 2013). SELECTION CRITERIA: Randomised trials (published or unpublished) comparing Pseudomonas aeruginosa vaccines (oral, parenteral or intranasal) with control vaccines or no intervention in cystic...

Protein carriers of conjugate vaccines: characteristics, development, and clinical trials.

Science.gov (United States)

Pichichero, Michael E

2013-12-01

The immunogenicity of polysaccharides as human vaccines was enhanced by coupling to protein carriers. Conjugation transformed the T cell-independent polysaccharide vaccines of the past to T cell-dependent antigenic vaccines that were much more immunogenic and launched a renaissance in vaccinology. This review discusses the conjugate vaccines for prevention of infections caused by Hemophilus influenzae type b, Streptococcus pneumoniae, and Neisseria meningitidis. Specifically, the characteristics of the proteins used in the construction of the vaccines including CRM, tetanus toxoid, diphtheria toxoid, Neisseria meningitidis outer membrane complex, and Hemophilus influenzae protein D are discussed. The studies that established differences among and key features of conjugate vaccines including immunologic memory induction, reduction of nasopharyngeal colonization and herd immunity, and antibody avidity and avidity maturation are presented. Studies of dose, schedule, response to boosters, of single protein carriers with single and multiple polysaccharides, of multiple protein carriers with multiple polysaccharides and conjugate vaccines administered concurrently with other vaccines are discussed along with undesirable consequences of conjugate vaccines. The clear benefits of conjugate vaccines in improving the protective responses of the immature immune systems of young infants and the senescent immune systems of the elderly have been made clear and opened the way to development of additional vaccines using this technology for future vaccine products.

R&D in Vaccines Targeting Neglected Diseases: An Exploratory Case Study Considering Funding for Preventive Tuberculosis Vaccine Development from 2007 to 2014.

Science.gov (United States)

Costa Barbosa Bessa, Theolis; Santos de Aragão, Erika; Medeiros Guimarães, Jane Mary; de Araújo Almeida, Bethânia

2017-01-01

Based on an exploratory case study regarding the types of institutions funding the research and development to obtain new tuberculosis vaccines, this article intends to provoke discussion regarding the provision of new vaccines targeting neglected disease. Although our findings and discussion are mainly relevant to the case presented here, some aspects are more generally applicable, especially regarding the dynamics of development in vaccines to prevent neglected diseases. Taking into account the dynamics of innovation currently seen at work in the vaccine sector, a highly concentrated market dominated by few multinational pharmaceutical companies, we feel that global PDP models can play an important role throughout the vaccine development cycle. In addition, the authors call attention to issues surrounding the coordination of actors and resources in the research, development, manufacturing, and distribution processes of vaccine products arising from PDP involvement.

Pharmacoeconomic spotlight on rotavirus vaccine RIX4414 (Rotarix™) in developed countries.

Science.gov (United States)

Plosker, Greg L

2012-12-01

The most common cause of severe diarrhea in infants and young children is rotavirus gastroenteritis (RVGE), which is associated with significant morbidity, healthcare resource use, and direct and indirect costs in industrialized nations. The monovalent rotavirus vaccine RIX4414 (Rotarix™) is administered as a two-dose oral series in infants and has demonstrated protective efficacy against RVGE in clinical trials conducted in developed countries. In addition, various naturalistic studies have demonstrated 'real-world' effectiveness after the introduction of widespread rotavirus vaccination programs in the community setting. Numerous cost-effectiveness analyses have been conducted in developed countries in which a universal rotavirus vaccination program using RIX4414 was compared with no universal rotavirus vaccination program. There was a high degree of variability in base-case results across studies even when the studies were conducted in the same country, often reflecting differences in the selection of data sources or assumptions used to populate the models. In addition, results were sensitive to plausible changes in a number of key input parameters. As such, it is not possible to definitively state whether a universal rotavirus vaccination program with RIX4414 is cost effective in developed countries, although results of some analyses in some countries suggest this is the case. In addition, international guidelines advocate universal vaccination of infants and children against rotavirus. It is also difficult to draw conclusions regarding the cost effectiveness of rotavirus vaccine RIX4414 relative to that of the pentavalent rotavirus vaccine, which is administered as a three-dose oral series. Although indirect comparisons in cost-effectiveness analyses indicate that RIX4414 provided more favorable incremental cost-effectiveness ratios when each vaccine was compared with no universal rotavirus vaccination program, results were generally sensitive to vaccine

Live attenuated hepatitis A vaccines developed in China

Science.gov (United States)

Xu, Zhi-Yi; Wang, Xuan-Yi

2014-01-01

Two live, attenuated hepatitis A vaccines, H2 and LA-1 virus strains, were developed through serial passages of the viruses in cell cultures at 32 °C and 35 °C respectively. Both vaccines were safe and immunogenic, providing protection against clinical hepatitis A in 95% of the vaccinees, with a single dose by subcutaneous injection. The vaccine recipients were not protected from asymptomatic, subclinical hepatitis A virus (HAV) infection, which induced a similar antibody response as for unvaccinated subjects. A second dose caused anamnestic response and can be used for boosting. Oral immunization of human with H2 vaccine or of marmoset with LA-1 vaccine failed, and no evidence was found for person-to-person transmission of H2 strain or for marmoset-to-marmoset transmission of LA-1 strain by close contact. H2 strain was genetically stable when passaged in marmosets, humans or cell cultures at 37 °C; 3 consecutive passages of the virus in marmosets did not cause virulence mutation. The live vaccines offer the benefits of low cost, single dose injection, long- term protection, and increased duration of immunity through subclinical infection. Improved sanitation and administration of 150 million doses of the live vaccines to children had led to a 90% reduction in the annual national incidence rate of hepatitis A in China during the 16-year period, from 1991 to 2006. Hepatitis A (HA) immunization with both live and inactivated HA vaccines was implemented in the national routine childhood immunization program in 2008 and around 92% of the 16 million annual births received the affordable live, attenuated vaccines at 18 months of age. Near elimination of the disease was achieved in a county of China for 14 years following introduction of the H2 live vaccine into the Expanded Immunization Program (EPI) in 1992. PMID:24280971

[Vaccine for human immunodeficiency virus (HIV)--relevance of these days].

Science.gov (United States)

Laiskonis, Alvydas; Pukenyte, Evelina

2005-01-01

Since 1980 more than 25 million people have died from acquired immunodeficiency syndrome (AIDS), which results from infection with human immunodeficiency virus (HIV). Number of new cases increases very threateningly. One and the most effective method to stop the progress of epidemic is the development of the vaccine for HIV. There is the presentation of the first stage of the vaccine for HIV testing (structure, methodology), which is now on trial in St. Pierre hospital, Brussels University. HIV characteristics which inflame the process of the vaccine development, historical facts and facts about vaccines on trial in these days are reviewed in this article. More than 10,000 volunteers have been participating in various clinical trials since 1987. The development of the vaccine is a very difficult, long-terming (about 8-10 years) and costly process. The process of the vaccine testing is very difficult in developing countries where the infection spreads the most rapidly. Available data confirm that the vaccine must be multi-componential, inducing cellular, humoral immunity against various subtypes of HIV. The vaccine cannot protect fully but the changes of the natural infection course could decrease virulence, distance the stage of AIDS, and retard the spread of the epidemic.

Current status of syphilis vaccine development: need, challenges, prospects.

Science.gov (United States)

Cameron, Caroline E; Lukehart, Sheila A

2014-03-20

Syphilis is a multistage disease caused by the invasive spirochete Treponema pallidum subsp. pallidum. Despite inexpensive and effective antibiotic therapy, syphilis remains a prevalent disease in developing countries and has re-emerged as a public health threat in developed nations. In addition to the medical burden imparted by infectious syphilis, congenital syphilis is considered the most significant infectious disease affecting fetuses and newborns worldwide, and individuals afflicted with syphilis have an enhanced risk for HIV transmission and acquisition. The global disease burden of syphilis and failure of decades of public health efforts to stem the incidence of disease highlight the need for an effective syphilis vaccine. Although challenges associated with T. pallidum research have impeded understanding of this pathogen, the existence of a relevant animal model has enabled insight into the correlates of disease protection. Complete protection against infection has been achieved in the animal model using an extended immunization regimen of γ-irradiated T. pallidum, demonstrating the importance of treponemal surface components in generation of protective immunity and the feasibility of syphilis vaccine development. Syphilis is a prime candidate for development of a successful vaccine due to the (1) research community's accumulated knowledge of immune correlates of protection; (2) existence of a relevant animal model that enables effective pre-clinical analyses; (3) universal penicillin susceptibility of T. pallidum which enhances the attractiveness of clinical vaccine trials; and (4) significant public health benefit a vaccine would have on reduction of infectious/congenital syphilis and HIV rates. Critical personnel, research and market gaps need to be addressed before the goal of a syphilis vaccine can be realized, including recruitment of additional researchers to the T. pallidum research field with a proportional increase in research funding

Oral vaccination: where we are?

Science.gov (United States)

Silin, Dmytro S; Lyubomska, Oksana V; Jirathitikal, Vichai; Bourinbaiar, Aldar S

2007-07-01

As early as 900 years ago, the Bedouins of the Negev desert were reported to kill a rabid dog, roast its liver and feed it to a dog-bitten person for three to five days according to the size and number of bites [1] . In sixteenth century China, physicians routinely prescribed pills made from the fleas collected from sick cows, which purportedly prevented smallpox. One may dismiss the wisdom of the Bedouins or Chinese but the Nobel laureate, Charles Richet, demonstrated in 1900 that feeding raw meat can cure tuberculous dogs - an approach he termed zomotherapy. Despite historical clues indicating the feasibility of oral vaccination, this particular field is notoriously infamous for the abundance of dead-end leads. Today, most commercial vaccines are delivered by injection, which has the principal limitation that recipients do not like needles. In the last few years, there has been a sharp increase in interest in needle-free vaccine delivery; new data emerges almost daily in the literature. So far, there are very few licensed oral vaccines, but many more vaccine candidates are in development. Vaccines delivered orally have the potential to take immunization to a fundamentally new level. In this review, the authors summarize the recent progress in the area of oral vaccines.

EV-A71 vaccine licensure: a first step for multivalent enterovirus vaccine to control HFMD and other severe diseases.

Science.gov (United States)

Mao, Qunying; Wang, Yiping; Bian, Lianlian; Xu, Miao; Liang, Zhenglun

2016-07-20

Enteroviruses (EVs) are the most common viral agents in humans. Although most infections are mild or asymptomatic, there is a wide spectrum of clinical manifestations that may be caused by EV infections with varying degrees of severity. Among these viruses, EV-A71 and coxsackievirus (CV) CV-A16 from group A EVs attract the most attention because they are responsible for hand, foot and mouth disease (HFMD). Other EV-A viruses such as CV-A6 and CV-A10 were also reported to cause HFMD outbreaks in several countries or regions. Group B EVs such as CV-B3, CV-B5 and echovirus 30 were reported to be the main pathogens responsible for myocarditis and encephalitis epidemics and were also detected in HFMD patients. Vaccines are the best tools to control infectious diseases. In December 2015, China's Food and Drug Administration approved two inactivated EV-A71 vaccines for preventing severe HFMD.The CV-A16 vaccine and the EV-A71-CV-A16 bivalent vaccine showed substantial efficacy against HFMD in pre-clinical animal models. Previously, research on EV-B group vaccines was mainly focused on CV-B3 vaccine development. Because the HFMD pathogen spectrum has changed, and the threat from EV-B virus-associated severe diseases has gradually increased, it is necessary to develop multivalent HFMD vaccines. This study summarizes the clinical symptoms of diseases caused by EVs, such as HFMD, myocarditis and encephalitis, and the related EV vaccine development progress. In conclusion, developing multivalent EV vaccines should be strongly recommended to prevent HFMD, myocarditis, encephalitis and other severe diseases.

Organizing the HIV vaccine development effort.

Science.gov (United States)

Voronin, Yegor; Snow, William

2013-09-01

To describe and compare the diverse organizational structures and funding mechanisms applied to advance HIV preventive vaccine research and development and to help explain and inform evolving infrastructures and collaborative funding models. On the basis of models that have been tried, improved or abandoned over three decades, the field seems to have settled into a relatively stable set of diverse initiatives, each with its own organizational signature. At the same time, this set of organizations is forging cross-organizational collaborations, which promise to acquire newly emergent beneficial properties. Strong motivation to expedite HIV vaccine R&D has driven a diversity of customized and inventive organizational approaches, largely government and foundation funded. Although no one approach has proven a panacea, the field has evolved into a constellation of often overlapping organizations that complement or reinforce one another. The Global HIV Vaccine Enterprise, a responsive, rapidly evolving loose infrastructure, is an innovative collaboration to catalyze that evolution.

The introduction of new vaccines into developing countries. IV: Global Access Strategies.

Science.gov (United States)

Mahoney, Richard T; Krattiger, Anatole; Clemens, John D; Curtiss, Roy

2007-05-16

This paper offers a framework for managing a comprehensive Global Access Strategy for new vaccines in developing countries. It is aimed at strengthening the ability of public-sector entities to reach their goals. The Bill and Melinda Gates Foundation and The Rockefeller Foundation have been leaders in stimulating the creation of new organizations - public/private product development partnerships (PDPs) - that seek to accelerate vaccine development and distribution to meet the health needs of the world's poor. Case studies of two of these PDPs - the Salmonella Anti-pneumococcal Vaccine Program and the Pediatric Dengue Vaccine Initiative - examine development of such strategies. Relying on the application of innovation theory, the strategy leads to the identification of six Components of Innovation which cover all aspects of the vaccine innovation process. Appropriately modified, the proposed framework can be applied to the development and introduction of other products in developing countries including drugs, and nutritional and agricultural products.

The therapeutic potential of plant-derived vaccines and antibodies.

Science.gov (United States)

Rodgers, P B; Hamilton, W D; Adair, J R

1999-03-01

The production of recombinant proteins in plants is reviewed with a particular focus on plant-derived vaccines and antibodies for human healthcare. Issues relating to foreign gene expression, such as protein yield, localisation and glycosylation are also considered. Emphasis is placed on reporting progress with preclinical and clinical evaluation of plant-derived vaccines and antibodies. An assessment is made of the likely future direction of research and development in this area.

Development and Regulation of Novel Influenza Virus Vaccines: A United States Young Scientist Perspective.

Science.gov (United States)

Khurana, Surender

2018-04-27

Vaccination against influenza is the most effective approach for reducing influenza morbidity and mortality. However, influenza vaccines are unique among all licensed vaccines as they are updated and administered annually to antigenically match the vaccine strains and currently circulating influenza strains. Vaccine efficacy of each selected influenza virus vaccine varies depending on the antigenic match between circulating strains and vaccine strains, as well as the age and health status of the vaccine recipient. Low vaccine effectiveness of seasonal influenza vaccines in recent years provides an impetus to improve current seasonal influenza vaccines, and for development of next-generation influenza vaccines that can provide broader, long-lasting protection against both matching and antigenically diverse influenza strains. This review discusses a perspective on some of the issues and formidable challenges facing the development and regulation of the next-generation influenza vaccines.

Regulatory pathways for vaccines for developing countries.

Science.gov (United States)

Milstien, Julie; Belgharbi, Lahouari

2004-01-01

Vaccines that are designed for use only in developing countries face regulatory hurdles that may restrict their use. There are two primary reasons for this: most regulatory authorities are set up to address regulation of products for use only within their jurisdictions and regulatory authorities in developing countries traditionally have been considered weak. Some options for regulatory pathways for such products have been identified: licensing in the country of manufacture, file review by the European Medicines Evaluation Agency on behalf of WHO, export to a country with a competent national regulatory authority (NRA) that could handle all regulatory functions for the developing country market, shared manufacturing and licensing in a developing country with competent manufacturing and regulatory capacity, and use of a contracted independent entity for global regulatory approval. These options have been evaluated on the basis of five criteria: assurance of all regulatory functions for the life of the product, appropriateness of epidemiological assessment, applicability to products no longer used in the domestic market of the manufacturing country, reduction of regulatory risk for the manufacturer, and existing rules and regulations for implementation. No one option satisfies all criteria. For all options, national infrastructures (including the underlying regulatory legislative framework, particularly to formulate and implement local evidence-based vaccine policy) must be developed. WHO has led work to develop this capacity with some success. The paper outlines additional areas of action required by the international community to assure development and use of vaccines needed for the developing world. PMID:15042235

Green revolution vaccines, edible vaccines

African Journals Online (AJOL)

Admin

of development. Food vaccines may also help to suppress autoimmunity disorders such as Type-1. Diabetes. Key words: Edible vaccines, oral vaccines, antigen expression, food vaccines. INTRODUCTION. Vaccination involves the stimulation of the immune system to prepare it for the event of an invasion from a particular ...

The Current Status of the Disease Caused by Enterovirus 71 Infections: Epidemiology, Pathogenesis, Molecular Epidemiology, and Vaccine Development.

Science.gov (United States)

Chang, Ping-Chin; Chen, Shou-Chien; Chen, Kow-Tong

2016-09-09

Enterovirus 71 (EV71) infections have a major public health impact in the Asia-Pacific region. We reviewed the epidemiology, pathogenesis, and molecular epidemiology of EV71 infection as well as EV71 vaccine development. Previous studies were found using the search terms "enterovirus 71" and "epidemiology" or "pathogenesis" or "molecular epidemiology" or "vaccine" in Medline and PubMed. Articles that were not published in the English language, manuscripts without an abstract, and opinion articles were excluded from the review. The reported epidemiology of cases caused by EV71 infection varied from country to country; seasonal variations in incidence were observed. Most cases of EV71 infection that resulted in hospitalization for complications occurred in children less than five years old. The brainstem was the most likely major target of EV71 infection. The emergence of the EV71 epidemic in the Asia-Pacific region has been associated with the circulation of different genetic lineages (genotypes B3, B4, C1, C2, and C4) that appear to be undergoing rapid evolutionary changes. The relationship between the gene structure of the EV71 virus and the factors that ensure its survival, circulation, and evasion of immunity is still unknown. EV71 infection has emerged as an important global public health problem. Vaccine development, including the development of inactivated whole-virus live attenuated, subviral particles, and DNA vaccines, has been progressing.

Geneva-Seattle collaboration in support of developing country vaccine manufacturing.

Science.gov (United States)

Stevenson, Michael A

2018-04-01

Vaccines were once produced almost exclusively by state-supported entities. While they remain essential tools for public health protection, the majority of the world's governments have allowed industry to assume responsibility for this function. This is significant because while the international harmonisation of quality assurance standards have effectively increased vaccine safety, they have also reduced the number of developing country vaccine producers, and Northern multinational pharmaceutical companies have shown little interest in offering the range of low-priced products needed in low and middle-income-country contexts. This article examines how public-private collaboration is relevant to contemporary efforts aimed at strengthening developing country manufacturers' capacity to produce high-quality, low-priced vaccines. Specifically, it casts light on the important and largely complimentary roles of the World Health Organization, The Bill and Melinda Gates Foundation, and the Seattle-based non-profit PATH, in this process. The take away message is that external support remains critical to ensuring that developing country vaccine manufacturers have the tools needed to produce for both domestic and global markets, and the United Nations supply chain, and collaboration at the public-private interface is driving organisational innovation focused on meeting these goals.

[Towards a new vaccine economy?].

Science.gov (United States)

Poirot, P; Martin, J F

1994-01-01

When Jonas Salk announced in the mid-50s the availability of a new vaccine against poliomyelitis, the world had the impression that it was now controlling infectious diseases. In fact, the success of this vaccine has been considerable and although some innovations lead to the launch of vaccines against flu, measles, rubella or mumps, the world vaccine market remained remarkably stable till the mid-80s. However, since 1984 (launch of the hepatitis B vaccine) there have been very substantial changes and further change is expected in the next ten years in the world market. Today, big companies are making a concentrated supply: Pasteur Mérieux with its subsidiary Connaught, SmithKline Beecham who acquired the Belgian company RIT, and Merck & Co. who is joining its forces with Pasteur Mérieux. Medium sized and small companies remain and reflect the situation of the past, but must work hard to secure their long term existence eventhough the world demand is going to double before the year 2000. Very substantial technological innovations explain to a large extent the development of the supply: progress in molecular biology, and particularly genetic engineering, lead to recombinant vaccines of which hepatitis B is the best example with worldwide sales in the range of $600 million a year. Similarly, conjugation technologies have allowed the development of new vaccines against meningitis, particularly Haemophilus influenzae type b. More recently, an efficacious vaccine against hepatitis A has been launched and many new products will be marketed in the next years against herpes, Lyme disease, and agents of other meningitis, etc.(ABSTRACT TRUNCATED AT 250 WORDS)

Botulinum neurotoxin vaccines: Past history and recent developments.

Science.gov (United States)

Rusnak, Janice M; Smith, Leonard A

2009-12-01

Botulinum toxin may cause a neuroparalytic illness that may result in respiratory failure and require prolonged mechanical ventilation. As medical resources needed for supportive care of botulism in a bioterrorist event may quickly overwhelm the local healthcare systems, biodefense research efforts have been directed towards the development of a vaccine to prevent botulism. While human botulism has been caused only by toxin serotypes A, B, and E (rarely serotype F), all seven known immunologically distinct toxin serotypes (A - G) may potentially cause intoxication in humans from a bioterrorist event. A pentavalent (ABCDE) botulinum toxoid (PBT) has been administered as an investigation new drug (IND) to at-risk individuals for nearly 50 years. Due to declining immunogenicity of the PBT, research efforts have been directed at development of both improved (less local reactogenicity) botulinum toxoids and recombinant vaccines as potential vaccine candidates to replace the PBT.

Rotavirus vaccines

Directory of Open Access Journals (Sweden)

Kang G

2006-01-01

Full Text Available Rotavirus, the most common cause of severe diarrhea and a leading cause of mortality in children, has been a priority target for vaccine development for the past several years. The first rotavirus vaccine licensed in the United States was withdrawn because of an association of the vaccine with intussusception. However, the need for a vaccine is greatest in the developing world, because the benefits of preventing deaths due to rotavirus disease are substantially greater than the risk of intussusception. Early vaccines were based on animal strains. More recently developed and licenced vaccines are either animal-human reassortants or are based on human strains. In India, two candidate vaccines are in the development process, but have not yet reached efficacy trials. Many challenges regarding vaccine efficacy and safety remain. In addition to completing clinical evaluations of vaccines in development in settings with the highest disease burden and virus diversity, there is also a need to consider alternative vaccine development strategies.

Developing VISO: Vaccine Information Statement Ontology for patient education.

Science.gov (United States)

Amith, Muhammad; Gong, Yang; Cunningham, Rachel; Boom, Julie; Tao, Cui

2015-01-01

To construct a comprehensive vaccine information ontology that can support personal health information applications using patient-consumer lexicon, and lead to outcomes that can improve patient education. The authors composed the Vaccine Information Statement Ontology (VISO) using the web ontology language (OWL). We started with 6 Vaccine Information Statement (VIS) documents collected from the Centers for Disease Control and Prevention (CDC) website. Important and relevant selections from the documents were recorded, and knowledge triples were derived. Based on the collection of knowledge triples, the meta-level formalization of the vaccine information domain was developed. Relevant instances and their relationships were created to represent vaccine domain knowledge. The initial iteration of the VISO was realized, based on the 6 Vaccine Information Statements and coded into OWL2 with Protégé. The ontology consisted of 132 concepts (classes and subclasses) with 33 types of relationships between the concepts. The total number of instances from classes totaled at 460, along with 429 knowledge triples in total. Semiotic-based metric scoring was applied to evaluate quality of the ontology.

Development of improved pertussis vaccine.

Science.gov (United States)

Rumbo, Martin; Hozbor, Daniela

2014-01-01

Rates of infection with Bordetella pertussis, the gram-negative bacterium that causes the respiratory disease called whooping cough or pertussis, have not abated and 16 million cases with almost 200,000 deaths are estimated by the WHO to have occurred worldwide in 2008. Despite relatively high vaccination rates, the disease has come back in recent years to afflict people in numbers not seen since the pre-vaccine days. Indeed, pertussis is now recognized as a frequent infection not only in newborn and infants but also in adults. The disease symptoms also can be induced by the non-vaccine-preventable infection with the close species B. parapertussis for which an increasing number of cases have been reported. The epidemiologic situation and current knowledge of the limitations of pertussis vaccine point out the need to design improved vaccines. Several alternative approaches and their challenges are summarized.

Controlling dengue with vaccines in Thailand.

Directory of Open Access Journals (Sweden)

Dennis L Chao

Full Text Available Dengue is a mosquito-borne infectious disease that constitutes a growing global threat with the habitat expansion of its vectors Aedes aegyti and A. albopictus and increasing urbanization. With no effective treatment and limited success of vector control, dengue vaccines constitute the best control measure for the foreseeable future. With four interacting dengue serotypes, the development of an effective vaccine has been a challenge. Several dengue vaccine candidates are currently being tested in clinical trials. Before the widespread introduction of a new dengue vaccine, one needs to consider how best to use limited supplies of vaccine given the complex dengue transmission dynamics and the immunological interaction among the four dengue serotypes.We developed an individual-level (including both humans and mosquitoes, stochastic simulation model for dengue transmission and control in a semi-rural area in Thailand. We calibrated the model to dengue serotype-specific infection, illness and hospitalization data from Thailand. Our simulations show that a realistic roll-out plan, starting with young children then covering progressively older individuals in following seasons, could reduce local transmission of dengue to low levels. Simulations indicate that this strategy could avert about 7,700 uncomplicated dengue fever cases and 220 dengue hospitalizations per 100,000 people at risk over a ten-year period.Vaccination will have an important role in controlling dengue. According to our modeling results, children should be prioritized to receive vaccine, but adults will also need to be vaccinated if one wants to reduce community-wide dengue transmission to low levels.

Controlling Dengue with Vaccines in Thailand

Science.gov (United States)

Chao, Dennis L.; Halstead, Scott B.; Halloran, M. Elizabeth; Longini, Ira M.

2012-01-01

Background Dengue is a mosquito-borne infectious disease that constitutes a growing global threat with the habitat expansion of its vectors Aedes aegyti and A. albopictus and increasing urbanization. With no effective treatment and limited success of vector control, dengue vaccines constitute the best control measure for the foreseeable future. With four interacting dengue serotypes, the development of an effective vaccine has been a challenge. Several dengue vaccine candidates are currently being tested in clinical trials. Before the widespread introduction of a new dengue vaccine, one needs to consider how best to use limited supplies of vaccine given the complex dengue transmission dynamics and the immunological interaction among the four dengue serotypes. Methodology/Principal Findings We developed an individual-level (including both humans and mosquitoes), stochastic simulation model for dengue transmission and control in a semi-rural area in Thailand. We calibrated the model to dengue serotype-specific infection, illness and hospitalization data from Thailand. Our simulations show that a realistic roll-out plan, starting with young children then covering progressively older individuals in following seasons, could reduce local transmission of dengue to low levels. Simulations indicate that this strategy could avert about 7,700 uncomplicated dengue fever cases and 220 dengue hospitalizations per 100,000 people at risk over a ten-year period. Conclusions/Significance Vaccination will have an important role in controlling dengue. According to our modeling results, children should be prioritized to receive vaccine, but adults will also need to be vaccinated if one wants to reduce community-wide dengue transmission to low levels. PMID:23145197

Progression of rabbit haemorrhagic disease virus 2 upon vaccination in an industrial rabbitry: a laboratorial approach

OpenAIRE

C.L. Carvalho; E.L. Duarte; J.M. Monteiro; C. Afonso; J. Pacheco; P. Carvalho; P. Mendonça; A. Botelho; T. Albuquerque; P. Themudo; M. Fevereiro; A.M. Henriques; S.S. Santos Barros; M. Dias Duarte

2017-01-01

Rabbit haemorrhagic disease virus 2 (RHDV2) emerged recently in several European countries, leading to extensive economic losses in the industry. In response to this new infection, specific inactivated vaccines were developed in Europe and full and rapid setup of protective immunity induced by vaccination was reported. However, data on the efficacy of these vaccines in an ongoing-infection scenario is unavailable. In this study we investigated an infected RHDV2 indoor industrial meat rabbitry...

Gut-associated lymphoid tissues for the development of oral vaccines.

Science.gov (United States)

Kunisawa, Jun; Kurashima, Yosuke; Kiyono, Hiroshi

2012-05-01

Oral vaccine has been considered to be a prospective vaccine against many pathogens especially invading across gastrointestinal tracts. One key element of oral vaccine is targeting efficient delivery of antigen to gut-associated lymphoid tissue (GALT), the inductive site in the intestine where antigen-specific immune responses are initiated. Various chemical and biological antigen delivery systems have been developed and some are in clinical trials. In this review, we describe the immunological features of GALT and the current status of antigen delivery system candidates for successful oral vaccine. Copyright © 2011 Elsevier B.V. All rights reserved.

INTERNATIONAL EXPERIENCE OF ADMINISTRATION OF PNEUMOCOCCAL CONJUGATED VACCINES: PROBLEMS, PROGRESS, PERSPECTIVES

Directory of Open Access Journals (Sweden)

M.V. Fedoseenko

2009-01-01

Full Text Available This article presents the review of results of International conference on pneumococcal conjugated vaccines. Main results of international experience in the field of control of pneumococcal infection spreading are analyzed. Authors present modern data of clinical and economic effectiveness and safety of pneumococcal conjugated vaccine RCV-7, and describe experience of administration of vaccines of next generation – PCV-10 and PCV-13.Key words: children, pneumococcal infections, prophylaxis, vaccines.(Voprosy sovremennoi pediatrii — Current Pediatrics. 2009;8(1:130-134

Animal models for dengue vaccine development and testing.

Science.gov (United States)

Na, Woonsung; Yeom, Minjoo; Choi, Il-Kyu; Yook, Heejun; Song, Daesub

2017-07-01

Dengue fever is a tropical endemic disease; however, because of climate change, it may become a problem in South Korea in the near future. Research on vaccines for dengue fever and outbreak preparedness are currently insufficient. In addition, because there are no appropriate animal models, controversial results from vaccine efficacy assessments and clinical trials have been reported. Therefore, to study the mechanism of dengue fever and test the immunogenicity of vaccines, an appropriate animal model is urgently needed. In addition to mouse models, more suitable models using animals that can be humanized will need to be constructed. In this report, we look at the current status of model animal construction and discuss which models require further development.

Patent data mining: a tool for accelerating HIV vaccine innovation.

Science.gov (United States)

Clark, K; Cavicchi, J; Jensen, K; Fitzgerald, R; Bennett, A; Kowalski, S P

2011-05-31

Global access to advanced vaccine technologies is challenged by the interrelated components of intellectual property (IP) management strategies, technology transfer (legal and technical) capabilities and the capacity necessary for accelerating R&D, commercialization and delivery of vaccines. Due to a negative association with the management of IP, patents are often overlooked as a vast resource of freely available, information akin to scientific journals as well as business and technological information and trends fundamental for formulating policies and IP management strategies. Therefore, a fundamental step towards facilitating global vaccine access will be the assembly, organization and analysis of patent landscapes, to identify the amount of patenting, ownership (assignees) and fields of technology covered. This is critical for making informed decisions (e.g., identifying licensees, building research and product development collaborations, and ascertaining freedom to operate). Such information is of particular interest to the HIV vaccine community where the HIV Vaccine Enterprise, have voiced concern that IP rights (particularly patents and trade secrets) may prevent data and materials sharing, delaying progress in research and development of a HIV vaccine. We have compiled and analyzed a representative HIV vaccine patent landscape for a prime-boost, DNA/adenoviral vaccine platform, as an example for identifying obstacles, maximizing opportunities and making informed IP management strategy decisions towards the development and deployment of an efficacious HIV vaccine. Copyright © 2011 Elsevier Ltd. All rights reserved.

The Effect of Oral Vaccination with Mycobacterium bovis BCG on the Development of Tuberculosis in Captive European Badgers (Meles meles).

Science.gov (United States)

Chambers, Mark A; Aldwell, Frank; Williams, Gareth A; Palmer, Si; Gowtage, Sonya; Ashford, Roland; Dalley, Deanna J; Davé, Dipesh; Weyer, Ute; Salguero, Francisco J; Nunez, Alejandro; Nadian, Allan K; Crawshaw, Timothy; Corner, Leigh A L; Lesellier, Sandrine

2017-01-01

The European badger ( Meles meles ) is a reservoir host of Mycobacterium bovis and responsible for a proportion of the tuberculosis (TB) cases seen in cattle in the United Kingdom and Republic of Ireland. An injectable preparation of the bacillus Calmette-Guérin (BCG) vaccine is licensed for use in badgers in the UK and its use forms part of the bovine TB eradication plans of England and Wales. However, there are practical limitations to the widespread application of an injectable vaccine for badgers and a research priority is the development of an oral vaccine deliverable to badgers in bait. Previous studies reported the successful vaccination of badgers with oral preparations of 10 8 colony forming units (CFU) of both Pasteur and Danish strains of BCG contained within a lipid matrix composed of triglycerides of fatty acids. Protection against TB in these studies was expressed as a reduction in the number and apparent progression of visible lesions, and reductions in the bacterial load and dissemination of infection. To reduce the cost of an oral vaccine and reduce the potential for environmental contamination with BCG, it is necessary to define the minimal efficacious dose of oral BCG for badgers. The objectives of the two studies reported here were to compare the efficacy of BCG Danish strain in a lipid matrix with unformulated BCG given orally, and to evaluate the efficacy of BCG Danish in a lipid matrix at a 10-fold lower dose than previously evaluated in badgers. In the first study, both BCG unformulated and in a lipid matrix reduced the number and apparent progression of visible lesions and the dissemination of infection from the lung. In the second study, vaccination with BCG in the lipid matrix at a 10-fold lower dose produced a similar outcome, but with greater intra-group variability than seen with the higher dose in the first study. Further research is needed before we are able to recommend a final dose of BCG for oral vaccination of badgers against TB

Severe acute respiratory syndrome vaccine efficacy in ferrets: whole killed virus and adenovirus-vectored vaccines.

Science.gov (United States)

See, Raymond H; Petric, Martin; Lawrence, David J; Mok, Catherine P Y; Rowe, Thomas; Zitzow, Lois A; Karunakaran, Karuna P; Voss, Thomas G; Brunham, Robert C; Gauldie, Jack; Finlay, B Brett; Roper, Rachel L

2008-09-01

Although the 2003 severe acute respiratory syndrome (SARS) outbreak was controlled, repeated transmission of SARS coronavirus (CoV) over several years makes the development of a SARS vaccine desirable. We performed a comparative evaluation of two SARS vaccines for their ability to protect against live SARS-CoV intranasal challenge in ferrets. Both the whole killed SARS-CoV vaccine (with and without alum) and adenovirus-based vectors encoding the nucleocapsid (N) and spike (S) protein induced neutralizing antibody responses and reduced viral replication and shedding in the upper respiratory tract and progression of virus to the lower respiratory tract. The vaccines also diminished haemorrhage in the thymus and reduced the severity and extent of pneumonia and damage to lung epithelium. However, despite high neutralizing antibody titres, protection was incomplete for all vaccine preparations and administration routes. Our data suggest that a combination of vaccine strategies may be required for effective protection from this pathogen. The ferret may be a good model for SARS-CoV infection because it is the only model that replicates the fever seen in human patients, as well as replicating other SARS disease features including infection by the respiratory route, clinical signs, viral replication in upper and lower respiratory tract and lung damage.

Current barriers, challenges and opportunities for the development of effective STI vaccines: point of view of vaccine producers, biotech companies and funding agencies.

Science.gov (United States)

Dodet, Betty

2014-03-20

Several barriers limit the development of vaccines against sexually transmitted diseases (STIs). Critical scientific information is missing that makes the feasibility and the likelihood of success of vaccines against genital herpes, chlamydia, gonorrhea and trichomonas uncertain: the immunity induced by natural infection is absent or imperfect which seriously limits the capacity to define the types of immune responses that an effective vaccine must induce. Reliable animal models are lacking and a number of crucial clinical questions are still unanswered about the goal of these vaccines and definition of endpoints for clinical trials. In the absence of a clear recognition of the need for vaccines against these diseases, there is no motivation for public or private research and industry to invest in the development of vaccines against STIs. The STI burden should be evaluated not only in terms of mortality and morbidity, but also in terms of economic and psycho-social impact. A global public-private consortium could mobilize the joint efforts of all stakeholders involved in the research, development and implementation of STI vaccines of the public and private sectors; ensure that sufficient resources are applied to R&D of vaccines against these STIs; and provide the pull-push forces that are necessary to overcome the barriers to develop safe and effective vaccines against these diseases. Copyright © 2014. Published by Elsevier Ltd.

DNA/MVA Vaccines for HIV/AIDS

Directory of Open Access Journals (Sweden)

Smita S. Iyer

2014-02-01

Full Text Available Since the initial proof-of-concept studies examining the ability of antigen-encoded plasmid DNA to serve as an immunogen, DNA vaccines have evolved as a clinically safe and effective platform for priming HIV-specific cellular and humoral responses in heterologous “prime-boost” vaccination regimens. Direct injection of plasmid DNA into the muscle induces T- and B-cell responses against foreign antigens. However, the insufficient magnitude of this response has led to the development of approaches for enhancing the immunogenicity of DNA vaccines. The last two decades have seen significant progress in the DNA-based vaccine platform with optimized plasmid constructs, improved delivery methods, such as electroporation, the use of molecular adjuvants and novel strategies combining DNA with viral vectors and subunit proteins. These innovations are paving the way for the clinical application of DNA-based HIV vaccines. Here, we review preclinical studies on the DNA-prime/modified vaccinia Ankara (MVA-boost vaccine modality for HIV. There is a great deal of interest in enhancing the immunogenicity of DNA by engineering DNA vaccines to co-express immune modulatory adjuvants. Some of these adjuvants have demonstrated encouraging results in preclinical and clinical studies, and these data will be examined, as well.

Herpes Simplex Vaccines: Prospects of Live-attenuated HSV Vaccines to Combat Genital and Ocular infections

Science.gov (United States)

Stanfield, Brent; Kousoulas, Konstantin Gus

2015-01-01

Herpes simplex virus type-1 (HSV-1) and its closely related type-2 (HSV-2) viruses cause important clinical manifestations in humans including acute ocular disease and genital infections. These viruses establish latency in the trigeminal ganglionic and dorsal root neurons, respectively. Both viruses are widespread among humans and can frequently reactivate from latency causing disease. Currently, there are no vaccines available against herpes simplex viral infections. However, a number of promising vaccine approaches are being explored in pre-clinical investigations with few progressing to early phase clinical trials. Consensus research findings suggest that robust humoral and cellular immune responses may partially control the frequency of reactivation episodes and reduce clinical symptoms. Live-attenuated viral vaccines have long been considered as a viable option for generating robust and protective immune responses against viral pathogens. Varicella zoster virus (VZV) belongs to the same alphaherpesvirus subfamily with herpes simplex viruses. A live-attenuated VZV vaccine has been extensively used in a prophylactic and therapeutic approach to combat primary and recurrent VZV infection indicating that a similar vaccine approach may be feasible for HSVs. In this review, we summarize pre-clinical approaches to HSV vaccine development and current efforts to test certain vaccine approaches in human clinical trials. Also, we discuss the potential advantages of using a safe, live-attenuated HSV-1 vaccine strain to protect against both HSV-1 and HSV-2 infections. PMID:27114893

Development of marker vaccines for rinderpest virus using reverse genetics technology

International Nuclear Information System (INIS)

Parida, S.; Walsh, E.P.; Anderson, J.; Baron, M.D.; Barrett, T.

2005-01-01

Rinderpest is an economically devastating disease of cattle (cattle plague), but a live-attenuated vaccine has been very successfully used in a global rinderpest eradication campaign. As a consequence, the endemic focus of the virus has been reduced to an area in eastern Africa known as the Kenya-Somali ecosystem. Although the vaccine is highly effective, it has a drawback in that vaccinated animals are serologically indistinguishable from those that have recovered from natural infection. In the final stages of the eradication campaign, when vaccination to control the spread of disease will only be used in emergencies to contain an outbreak, a marker vaccine would be a very useful tool to monitor possible wild virus spread outside the vaccination area. Marker vaccines for rinderpest, and other viruses with negative-sense RNA genomes, can now be produced using reverse genetics, and the development of such marker vaccines for rinderpest virus is described. (author)

Probability to produce animal vaccines in insect baculovirus ...

African Journals Online (AJOL)

The insect baculovirus expression system is a valuable tool for the production of vaccine. Many subunit vaccines have been expressed in this system. The first vaccine produced in insect cells for animal use is now in the market. In this study, we reviewed recent progress of animal's vaccine production for different expression ...

Ontology-supported research on vaccine efficacy, safety and integrative biological networks.

Science.gov (United States)

He, Yongqun

2014-07-01

While vaccine efficacy and safety research has dramatically progressed with the methods of in silico prediction and data mining, many challenges still exist. A formal ontology is a human- and computer-interpretable set of terms and relations that represent entities in a specific domain and how these terms relate to each other. Several community-based ontologies (including Vaccine Ontology, Ontology of Adverse Events and Ontology of Vaccine Adverse Events) have been developed to support vaccine and adverse event representation, classification, data integration, literature mining of host-vaccine interaction networks, and analysis of vaccine adverse events. The author further proposes minimal vaccine information standards and their ontology representations, ontology-based linked open vaccine data and meta-analysis, an integrative One Network ('OneNet') Theory of Life, and ontology-based approaches to study and apply the OneNet theory. In the Big Data era, these proposed strategies provide a novel framework for advanced data integration and analysis of fundamental biological networks including vaccine immune mechanisms.

Progressive decrease in the potential usefulness of meningococcal serogroup B vaccine (4CMenB, Bexsero® in Gipuzkoa, Northern Spain.

Directory of Open Access Journals (Sweden)

Emilio Pérez-Trallero

Full Text Available The effectiveness of a vaccine is determined not only by the immunogenicity of its components, but especially by how widely it covers the disease-causing strains circulating in a given region. Because vaccine coverage varies over time, this study aimed to detect possible changes that could affect vaccine protection during a specific period in a southern European region. The 4CMenB vaccine is licensed for use in Europe, Canada, and Australia and is mainly directed against Neisseria meningitidis serogroup B. This vaccine contains four main immunogenic components: three recombinant proteins, FHbp, Nhba and NadA, and an outer membrane vesicle [PorA P1.4]. The allelic distribution of FHbp, Nhba, NadA, and PorA antigens in 82 invasive isolates (B and non-B serogroups isolated from January 2008 to December 2013 were analyzed. 4CMenB was likely protective against 61.8% and 50% of serogroup B and non-B meningococci, respectively, in the entire period, but between 2012 and 2013, the predicted protection fell below 45% (42.1% for serogroup B isolates.The observed decreasing trend in the predicted protection during the 6 years of the study (Χ2 for trend  = 4.68, p = 0.03 coincided with a progressive decrease of several clonal complexes (e.g., cc11, cc32 and cc41/44, which had one or more antigens against which the vaccine would offer protection.

Mucosal vaccines: a paradigm shift in the development of mucosal adjuvants and delivery vehicles.

Science.gov (United States)

Srivastava, Atul; Gowda, Devegowda Vishakante; Madhunapantula, SubbaRao V; Shinde, Chetan G; Iyer, Meenakshi

2015-04-01

Mucosal immune responses are the first-line defensive mechanisms against a variety of infections. Therefore, immunizations of mucosal surfaces from which majority of infectious agents make their entry, helps to protect the body against infections. Hence, vaccinization of mucosal surfaces by using mucosal vaccines provides the basis for generating protective immunity both in the mucosal and systemic immune compartments. Mucosal vaccines offer several advantages over parenteral immunization. For example, (i) ease of administration; (ii) non-invasiveness; (iii) high-patient compliance; and (iv) suitability for mass vaccination. Despite these benefits, to date, only very few mucosal vaccines have been developed using whole microorganisms and approved for use in humans. This is due to various challenges associated with the development of an effective mucosal vaccine that can work against a variety of infections, and various problems concerned with the safe delivery of developed vaccine. For instance, protein antigen alone is not just sufficient enough for the optimal delivery of antigen(s) mucosally. Hence, efforts have been made to develop better prophylactic and therapeutic vaccines for improved mucosal Th1 and Th2 immune responses using an efficient and safe immunostimulatory molecule and novel delivery carriers. Therefore, in this review, we have made an attempt to cover the recent advancements in the development of adjuvants and delivery carriers for safe and effective mucosal vaccine production. © 2015 APMIS. Published by John Wiley & Sons Ltd.

Therapeutic Vaccination for HPV Induced Cervical Cancers

Directory of Open Access Journals (Sweden)

Joeli A. Brinkman

2007-01-01

Full Text Available Cervical Cancer is the second leading cause of cancer–related deaths in women worldwide and is associated with Human Papillomavirus (HPV infection, creating a unique opportunity to treat cervical cancer through anti-viral vaccination. Although a prophylactic vaccine may be available within a year, millions of women, already infected, will continue to suffer from HPV-related disease, emphasizing the need to develop therapeutic vaccination strategies. A majority of clinical trials examining therapeutic vaccination have shown limited efficacy due to examining patients with more advanced-stage cancer who tend to have decreased immune function. Current trends in clinical trials with therapeutic agents examine patients with pre-invasive lesions in order to prevent invasive cervical cancer. However, longer follow-up is necessary to correlate immune responses to lesion regression. Meanwhile, preclinical studies in this field include further exploration of peptide or protein vaccination, and the delivery of HPV antigens in DNA-based vaccines or in viral vectors. As long as pre-clinical studies continue to advance, the prospect of therapeutic vaccination to treat existing lesions seem good in the near future. Positive consequences of therapeutic vaccination would include less disfiguring treatment options and fewer instances of recurrent or progressive lesions leading to a reduction in cervical cancer incidence.

Bovine rotavirus pentavalent vaccine development in India.

Science.gov (United States)

Zade, Jagdish K; Kulkarni, Prasad S; Desai, Sajjad A; Sabale, Rajendra N; Naik, Sameer P; Dhere, Rajeev M

2014-08-11

A bovine rotavirus pentavalent vaccine (BRV-PV) containing rotavirus human-bovine (UK) reassortant strains of serotype G1, G2, G3, G4 and G9 has been developed by the Serum Institute of India Ltd, in collaboration with the National Institute of Allergy and Infectious Diseases (NIAID), USA. The vaccine underwent animal toxicity studies and Phase I and II studies in adults, toddlers and infants. It has been found safe and immunogenic and will undergo a large Phase III study to assess efficacy against severe rotavirus gastroenteritis. Copyright © 2014. Published by Elsevier Ltd.

Dengue vaccine: come let's fight the menace.

Science.gov (United States)

Chawla, Sumit; Sahoo, Soumya Swaroop; Singh, Inderjeet; Verma, Madhur; Gupta, Vikas; Kumari, Sneh

2015-01-01

Although dengue has a global distribution, the World Health Organization (WHO) South-East Asia region together with Western Pacific region bears nearly 75% of the current global disease burden. Globally, the societal burden has been estimated to be approximately 528 to 1300 disability-adjusted life years (DALY) per million to populations in endemic regions Dengue is believed to infect 50 to 100 million people worldwide a year with half a million life-threatening infections requiring hospitalization, resulting in approximately 12,500 to 25,000 deaths. Despite being known for decades and nearly half the world's population is at risk for infection with as many as 100 million cases occurring annually, the pitiable state is that we still have no antiviral drugs to treat it and no vaccines to prevent it. In recent years, however, the development of dengue vaccines has accelerated dramatically in tandem with the burgeoning dengue problem with a rejuvenated vigour. However, recent progress in molecular-based vaccine strategies, as well as a renewed commitment by the World Health Organization (WHO) to co-ordinate global efforts on vaccine development, finally provides hope that control of this serious disease may be at hand. Today, several vaccines are in various stages of advanced development, with clinical trials currently underway on 5 candidate vaccines. Trials in the most advanced stages are showing encouraging preliminary data, and the leading candidate could be licensed as early as 2015.

Development, Production, and Postmarketing Surveillance of Hepatitis A Vaccines in China

Science.gov (United States)

Cui, Fuqiang; Liang, Xiaofeng; Wang, Fuzhen; Zheng, Hui; Hutin, Yvan J; Yang, Weizhong

2014-01-01

China has long experience using live attenuated and inactivated vaccines against hepatitis A virus (HAV) infection. We summarize this experience and provide recent data on adverse events after immunization (AEFIs) with hepatitis A vaccines in China. We reviewed the published literature (in Chinese and English) and the published Chinese regulatory documents on hepatitis A vaccine development, production, and postmarketing surveillance of AEFI. We described the safety, immunogenicity, and efficacy of hepatitis A vaccines and horizontal transmission of live HAV vaccine in China. In clinical trials, live HAV vaccine was associated with fever (0.4%–5% of vaccinees), rash (0%–1.1%), and elevated alanine aminotransferase (0.015%). Inactivated HAV vaccine was associated with fever (1%–8%), but no serious AEFIs were reported. Live HAV vaccine had seroconversion rates of 83% to 91%, while inactivated HAV vaccine had seroconversion rates of 95% to 100%. Community trials showed efficacy rates of 90% to 95% for live HAV and 95% to 100% for inactivated HAV vaccine. Postmarketing surveillance showed that HAV vaccination resulted in an AEFI incidence rate of 34 per million vaccinees, which accounted for 0.7% of adverse events reported to the China AEFI monitoring system. There was no difference in AEFI rates between live and inactivated HAV vaccines. Live and inactivated HAV vaccines manufactured in China were immunogenic, effective, and safe. Live HAV vaccine had substantial horizontal transmission due to vaccine virus shedding; thus, further monitoring of the safety of virus shedding is warranted. PMID:24681843

Visceral Leishmaniasis: Advancements in vaccine development via classical and molecular approaches

Directory of Open Access Journals (Sweden)

Sumit eJoshi

2014-08-01

Full Text Available Visceral Leishmaniasis (VL or kala-azar, a vector-borne protozoan disease, shows endemicity in larger areas of the tropical, subtropical and the Mediterranean countries. WHO report suggested that nearly 500,000 new cases of VL occur annually, including 100,000 cases from India itself. Treatment with available anti-leishmanial drugs are not cost effective, with varied efficacies and higher relapse rate, which poses a major challenge to current kala-azar control program in Indian subcontinent. Therefore, a vaccine against VL is imperative and knowing the fact that recovered individuals developed lifelong immunity against re-infection, it is feasible. Vaccine development program, though time taking, has recently gained momentum with the emergence of omic era i.e. from genomics to immunomics. Classical as well as molecular methodologies has been overtaken with alternative strategies wherein proteomics based knowledge combined with computational techniques (immunoinformatics speed up the identification and detailed characterization of new antigens for potential vaccine candidates. This may eventually help in the designing of polyvalent synthetic and recombinant chimeric vaccines as an effective intervention measures to control the disease in endemic areas. This review focuses on such newer approaches being utilized for vaccine development against VL.

Development and introduction of inactivated poliovirus vaccines derived from Sabin strains in Japan.

Science.gov (United States)

Shimizu, Hiroyuki

2016-04-07

During the endgame of global polio eradication, the universal introduction of inactivated poliovirus vaccines is urgently required to reduce the risk of vaccine-associated paralytic poliomyelitis and polio outbreaks due to wild and vaccine-derived polioviruses. In particular, the development of inactivated poliovirus vaccines (IPVs) derived from the attenuated Sabin strains is considered to be a highly favorable option for the production of novel IPV that reduce the risk of facility-acquired transmission of poliovirus to the communities. In Japan, Sabin-derived IPVs (sIPVs) have been developed and introduced for routine immunization in November 2012. They are the first licensed sIPVs in the world. Consequently, trivalent oral poliovirus vaccine was used for polio control in Japan for more than half a century but has now been removed from the list of vaccines licensed for routine immunization. This paper reviews the development, introduction, characterization, and global status of IPV derived from attenuated Sabin strains. Copyright © 2014 Elsevier Ltd. All rights reserved.

Development of hypertrophic osteodystrophy and antibody response in a litter of vaccinated Weimaraner puppies.

Science.gov (United States)

Harrus, S; Waner, T; Aizenberg; Safra, N; Mosenco, A; Radoshitsky, M; Bark, H

2002-01-01

Two different vaccination protocols were compared with regard to the development of hypertrophic osteodystrophy (HOD) (also termed metaphyseal osteopathy) and effectiveness of immunisation in a litter of 10 Weimaraner puppies. Five puppies (group 1) were vaccinated with a modified live canine parvovirus vaccine (CPV) and then two weeks later with a trivalent vaccine containing modified live canine distemper virus and adenovirus type 2 combined with a Leptospira bacterin (DHL). The CPV and DHL vaccine protocols were administered a further two times, at two-week intervals. Group 2 was vaccinated with three consecutive multivalent vaccines containing modified live canine distemper virus, canine parvovirus, parainfluenza and adenovirus type 2 combined with a Leptospira bacterin, at four-week intervals. All puppies were first vaccinated at the age of eight weeks. Three dogs in group 1 developed HOD, while all five dogs in group 2 developed HOD during the study period. Dogs in group 2 had more episodes of HOD than those in group 1. Dogs in group 1 developed higher antibody titres to canine distemper virus and parvovirus compared with those in group 2. Only two out of the 10 dogs developed protective antibody titres to parvovirus. The results of this study suggest that the two different vaccination protocols affected the pattern of appearance of HOD and immunisation in this litter of Weimaraner puppies. The results obtained and the previously reported data suggest that a larger controlled study is needed to further elucidate the effect of different vaccination protocols on HOD and immunisation in Weimaraner puppies.

Informing vaccine decision-making: A strategic multi-attribute ranking tool for vaccines-SMART Vaccines 2.0.

Science.gov (United States)

Knobler, Stacey; Bok, Karin; Gellin, Bruce

2017-01-20

SMART Vaccines 2.0 software is being developed to support decision-making among multiple stakeholders in the process of prioritizing investments to optimize the outcomes of vaccine development and deployment. Vaccines and associated vaccination programs are one of the most successful and effective public health interventions to prevent communicable diseases and vaccine researchers are continually working towards expanding targets for communicable and non-communicable diseases through preventive and therapeutic modes. A growing body of evidence on emerging vaccine technologies, trends in disease burden, costs associated with vaccine development and deployment, and benefits derived from disease prevention through vaccination and a range of other factors can inform decision-making and investment in new and improved vaccines and targeted utilization of already existing vaccines. Recognizing that an array of inputs influences these decisions, the strategic multi-attribute ranking method for vaccines (SMART Vaccines 2.0) is in development as a web-based tool-modified from a U.S. Institute of Medicine Committee effort (IOM, 2015)-to highlight data needs and create transparency to facilitate dialogue and information-sharing among decision-makers and to optimize the investment of resources leading to improved health outcomes. Current development efforts of the SMART Vaccines 2.0 framework seek to generate a weighted recommendation on vaccine development or vaccination priorities based on population, disease, economic, and vaccine-specific data in combination with individual preference and weights of user-selected attributes incorporating valuations of health, economics, demographics, public concern, scientific and business, programmatic, and political considerations. Further development of the design and utility of the tool is being carried out by the National Vaccine Program Office of the Department of Health and Human Services and the Fogarty International Center of the

Vaccination delays maedi-visna lentivirus infection in a naturally-infected sheep flock

Directory of Open Access Journals (Sweden)

Gudnadóttir Margrét

2013-01-01

Full Text Available Abstract Background The Maedi-Visna (MV lentivirus causes two slowly progressive eventually fatal diseases of sheep, Maedi, a progressive interstitial pneumonia, and Visna, a progressive demyelinating disease of the central nervous system. Other lentiviruses also cause fatal slow infections in their natural hosts, e.g. the HIV virus in humans. Results of experimental vaccination against any lentivirus where vaccinees are challenged by natural routes, may therefore be of general interest. From 1991–1998 experiments with formalin-inactivated whole Maedi-Visna virus vaccine were carried out in the Department of Microbiology at the University of Iceland. Western Blot tests showed good immune response to all major proteins of the virus. When aluminium hydroxide was added to the vaccine all vaccinees developed neutralizing antibodies to the vaccine strain at titers 1/8 – 1/256. After housing 5 twin pairs, one twin in each pair vaccinated, the other unvaccinated, with infected sheep for 4 years, all the unvaccinated twins became infected, but only 2 of their vaccinated siblings as confirmed by virus cultivation experiments on tissues from their lungs spleens lymph nodes and choroid plexuses. Results One twin in each of 40 female twin pairs, born into a Maedi-Visna-infected sheep flock and kept under natural farming conditions in Cyprus, was vaccinated at birth, 3 weeks and 3 months, with formalin-inactivated whole Maedi-Visna lentivirus vaccine adjuvanted with aluminium hydroxide. 17 mothers of the twins were seronegative, 13 seroconverting and 10 had old infection. Of 17 vaccinees born to seronegative mothers 9 were uninfected at 28 months, but only 2 of their unvaccinated siblings. Of 13 unvaccinated twins born to seroconverting mothers, 12 caught infection during their first 10 weeks, but only 4 of their vaccinated siblings. Vaccination had no effects on 10 vaccinees born to mothers with long-standing Maedi-Visna infections and broad andibody

Development of a recombinant toxin fragment vaccine for Clostridium difficile infection.

Science.gov (United States)

Karczewski, Jerzy; Zorman, Julie; Wang, Su; Miezeiewski, Matthew; Xie, Jinfu; Soring, Keri; Petrescu, Ioan; Rogers, Irene; Thiriot, David S; Cook, James C; Chamberlin, Mihaela; Xoconostle, Rachel F; Nahas, Debbie D; Joyce, Joseph G; Bodmer, Jean-Luc; Heinrichs, Jon H; Secore, Susan

2014-05-19

Clostridium difficile infection (CDI) is the major cause of antibiotic-associated diarrhea and pseudomembranous colitis, a disease associated with significant morbidity and mortality. The disease is mostly of nosocomial origin, with elderly patients undergoing anti-microbial therapy being particularly at risk. C. difficile produces two large toxins: Toxin A (TcdA) and Toxin B (TcdB). The two toxins act synergistically to damage and impair the colonic epithelium, and are primarily responsible for the pathogenesis associated with CDI. The feasibility of toxin-based vaccination against C. difficile is being vigorously investigated. A vaccine based on formaldehyde-inactivated Toxin A and Toxin B (toxoids) was reported to be safe and immunogenic in healthy volunteers and is now undergoing evaluation in clinical efficacy trials. In order to eliminate cytotoxic effects, a chemical inactivation step must be included in the manufacturing process of this toxin-based vaccine. In addition, the large-scale production of highly toxic antigens could be a challenging and costly process. Vaccines based on non-toxic fragments of genetically engineered versions of the toxins alleviate most of these limitations. We have evaluated a vaccine assembled from two recombinant fragments of TcdB and explored their potential as components of a novel experimental vaccine against CDI. Golden Syrian hamsters vaccinated with recombinant fragments of TcdB combined with full length TcdA (Toxoid A) developed high titer IgG responses and potent neutralizing antibody titers. We also show here that the recombinant vaccine protected animals against lethal challenge with C. difficile spores, with efficacy equivalent to the toxoid vaccine. The development of a two-segment recombinant vaccine could provide several advantages over toxoid TcdA/TcdB such as improvements in manufacturability. Copyright © 2014 Elsevier Ltd. All rights reserved.

Apicomplexan profilins in vaccine development applied to bovine neosporosis.

Science.gov (United States)

Mansilla, Florencia C; Capozzo, Alejandra V

2017-12-01

Neospora caninum, an intracellular protozoan parasite from the phylum Apicomplexa, is the etiologic agent of neosporosis, a disease considered as a major cause of reproductive loss in cattle and neuromuscular disease in dogs. Bovine neosporosis has a great economic impact in both meat and dairy industries, related to abortion, premature culling and reduced milk yields. Although many efforts have been made to restrain bovine neosporosis, there are still no efficacious control methods. Many vaccine-development studies focused in the apicomplexan proteins involved in the adhesion and invasion of the host cell. Among these proteins, profilins have recently emerged as potential vaccine antigens or even adjuvant candidates for several diseases caused by apicomplexan parasites. Profilins bind Toll-like receptors 11 and 12 initiating MyD88 signaling, that triggers IL-12 and IFN-γ production, which may promote protection against infection. Here we summarized the state-of-the-art of novel vaccine development based on apicomplexan profilins applied as antigens or adjuvants, and delved into recent advances on N. caninum vaccines using profilin in the mouse model and in cattle. Copyright © 2017 Elsevier Inc. All rights reserved.

Clinical development and regulatory points for consideration for second-generation live attenuated dengue vaccines.

Science.gov (United States)

Vannice, Kirsten S; Wilder-Smith, Annelies; Barrett, Alan D T; Carrijo, Kalinka; Cavaleri, Marco; de Silva, Aravinda; Durbin, Anna P; Endy, Tim; Harris, Eva; Innis, Bruce L; Katzelnick, Leah C; Smith, Peter G; Sun, Wellington; Thomas, Stephen J; Hombach, Joachim

2018-03-07

Licensing and decisions on public health use of a vaccine rely on a robust clinical development program that permits a risk-benefit assessment of the product in the target population. Studies undertaken early in clinical development, as well as well-designed pivotal trials, allow for this robust characterization. In 2012, WHO published guidelines on the quality, safety and efficacy of live attenuated dengue tetravalent vaccines. Subsequently, efficacy and longer-term follow-up data have become available from two Phase 3 trials of a dengue vaccine, conducted in parallel, and the vaccine was licensed in December 2015. The findings and interpretation of the results from these trials released both before and after licensure have highlighted key complexities for tetravalent dengue vaccines, including concerns vaccination could increase the incidence of dengue disease in certain subpopulations. This report summarizes clinical and regulatory points for consideration that may guide vaccine developers on some aspects of trial design and facilitate regulatory review to enable broader public health recommendations for second-generation dengue vaccines. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Intracellular Bacterial Infections: A Challenge for Developing Cellular Mediated Immunity Vaccines for Farmed Fish

Directory of Open Access Journals (Sweden)

Hetron Mweemba Munang’andu

2018-04-01

Full Text Available Aquaculture is one of the most rapidly expanding farming systems in the world. Its rapid expansion has brought with it several pathogens infecting different fish species. As a result, there has been a corresponding expansion in vaccine development to cope with the increasing number of infectious diseases in aquaculture. The success of vaccine development for bacterial diseases in aquaculture is largely attributed to empirical vaccine designs based on inactivation of whole cell (WCI bacteria vaccines. However, an upcoming challenge in vaccine design is the increase of intracellular bacterial pathogens that are not responsive to WCI vaccines. Intracellular bacterial vaccines evoke cellular mediated immune (CMI responses that “kill” and eliminate infected cells, unlike WCI vaccines that induce humoral immune responses whose protective mechanism is neutralization of extracellular replicating pathogens by antibodies. In this synopsis, I provide an overview of the intracellular bacterial pathogens infecting different fish species in aquaculture, outlining their mechanisms of invasion, replication, and survival intracellularly based on existing data. I also bring into perspective the current state of CMI understanding in fish together with its potential application in vaccine development. Further, I highlight the immunological pitfalls that have derailed our ability to produce protective vaccines against intracellular pathogens for finfish. Overall, the synopsis put forth herein advocates for a shift in vaccine design to include CMI-based vaccines against intracellular pathogens currently adversely affecting the aquaculture industry.

Development of novel vaccines using DNA shuffling and screening strategies.

Science.gov (United States)

Locher, Christopher P; Soong, Nay Wei; Whalen, Robert G; Punnonen, Juha

2004-02-01

DNA shuffling and screening technologies recombine and evolve genes in vitro to rapidly obtain molecules with improved biological activity and fitness. In this way, genes from related strains are bred like plants or livestock and their successive progeny are selected. These technologies have also been called molecular breeding-directed molecular evolution. Recent developments in bioinformatics-assisted computer programs have facilitated the design, synthesis and analysis of DNA shuffled libraries of chimeric molecules. New applications in vaccine development are among the key features of DNA shuffling and screening technologies because genes from several strains or antigenic variants of pathogens can be recombined to create novel molecules capable of inducing immune responses that protect against infections by multiple strains of pathogens. In addition, molecules such as co-stimulatory molecules and cytokines have been evolved to have improved T-cell proliferation and cytokine production compared with the wild-type human molecules. These molecules can be used to immunomodulate vaccine responsiveness and have multiple applications in infectious diseases, cancer, allergy and autoimmunity. Moreover, DNA shuffling and screening technologies can facilitate process development of vaccine manufacturing through increased expression of recombinant polypeptides and viruses. Therefore, DNA shuffling and screening technologies can overcome some of the challenges that vaccine development currently faces.

Vaccines for bovine neosporosis: current status and key aspects for development.

Science.gov (United States)

Horcajo, P; Regidor-Cerrillo, J; Aguado-Martínez, A; Hemphill, A; Ortega-Mora, L M

2016-12-01

Bovine neosporosis is a worldwide concern due to its global distribution and great economic impact. Reproductive failure in cattle due to abortion leads to major economic losses associated with the disease. Currently, there is no treatment or vaccine available against abortion or transmission caused by Neospora caninum infection in cattle. However, vaccination is considered the best measure of control against bovine neosporosis. Several host and parasite factors can influence the dynamics of the infection in bovines. Moreover, the availability of well-defined infection models is a key factor for the evaluation of vaccine candidates. However, working with cattle is not easy due to difficult handling, facilities and costs, and therefore, 'more affordable' models could be used for screening of promising vaccines to establish proof of concept. So far, live-attenuated vaccines have shown good efficacy against exogenous transplacental transmission; however, they have relevant disadvantages and associated risks, which render inactivated or subunit vaccines the best way forward. The identification of novel potential targets and vaccines, and the application of innovative vaccine technologies in harmonized experimental animal models, will accelerate the development of an effective vaccine against bovine neosporosis. © 2016 John Wiley & Sons Ltd.

Replacement of glycoprotein B in alcelaphine herpesvirus 1 by its ovine herpesvirus 2 homolog: Implications in vaccine development for sheep-associated malignant catarrhal fever

Science.gov (United States)

Vaccine development is a top priority in malignant catarrhal fever (MCF) research. In the case of sheep-associated MCF (SA-MCF), caused by ovine herpesvirus 2 (OvHV-2), progress towards this objective has been hindered by the absence of methods to attenuate or modify the virus, since it cannot be pr...

Plant-made oral vaccines against human infectious diseases-Are we there yet?

Science.gov (United States)

Chan, Hui-Ting; Daniell, Henry

2015-10-01

Although the plant-made vaccine field started three decades ago with the promise of developing low-cost vaccines to prevent infectious disease outbreaks and epidemics around the globe, this goal has not yet been achieved. Plants offer several major advantages in vaccine generation, including low-cost production by eliminating expensive fermentation and purification systems, sterile delivery and cold storage/transportation. Most importantly, oral vaccination using plant-made antigens confers both mucosal (IgA) and systemic (IgG) immunity. Studies in the past 5 years have made significant progress in expressing vaccine antigens in edible leaves (especially lettuce), processing leaves or seeds through lyophilization and achieving antigen stability and efficacy after prolonged storage at ambient temperatures. Bioencapsulation of antigens in plant cells protects them from the digestive system; the fusion of antigens to transmucosal carriers enhances efficiency of their delivery to the immune system and facilitates successful development of plant vaccines as oral boosters. However, the lack of oral priming approaches diminishes these advantages because purified antigens, cold storage/transportation and limited shelf life are still major challenges for priming with adjuvants and for antigen delivery by injection. Yet another challenge is the risk of inducing tolerance without priming the host immune system. Therefore, mechanistic aspects of these two opposing processes (antibody production or suppression) are discussed in this review. In addition, we summarize recent progress made in oral delivery of vaccine antigens expressed in plant cells via the chloroplast or nuclear genomes and potential challenges in achieving immunity against infectious diseases using cold-chain-free vaccine delivery approaches. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

Intestinal Pathogenic Escherichia coli: Insights for Vaccine Development

Directory of Open Access Journals (Sweden)

Maricarmen Rojas-Lopez

2018-03-01

Full Text Available Diarrheal diseases are one of the major causes of mortality among children under five years old and intestinal pathogenic Escherichia coli (InPEC plays a role as one of the large causative groups of these infections worldwide. InPECs contribute significantly to the burden of intestinal diseases, which are a critical issue in low- and middle-income countries (Asia, Africa and Latin America. Intestinal pathotypes such as enteropathogenic E. coli (EPEC and enterotoxigenic E. coli (ETEC are mainly endemic in developing countries, while ETEC strains are the major cause of diarrhea in travelers to these countries. On the other hand, enterohemorrhagic E. coli (EHEC are the cause of large outbreaks around the world, mainly affecting developed countries and responsible for not only diarrheal disease but also severe clinical complications like hemorrhagic colitis and hemolytic uremic syndrome (HUS. Overall, the emergence of antibiotic resistant strains, the annual cost increase in the health care system, the high incidence of traveler diarrhea and the increased number of HUS episodes have raised the need for effective preventive treatments. Although the use of antibiotics is still important in treating such infections, non-antibiotic strategies are either a crucial option to limit the increase in antibiotic resistant strains or absolutely necessary for diseases such as those caused by EHEC infections, for which antibiotic therapies are not recommended. Among non-antibiotic therapies, vaccine development is a strategy of choice but, to date, there is no effective licensed vaccine against InPEC infections. For several years, there has been a sustained effort to identify efficacious vaccine candidates able to reduce the burden of diarrheal disease. The aim of this review is to summarize recent milestones and insights in vaccine development against InPECs.

76 FR 49776 - The Development and Evaluation of Next-Generation Smallpox Vaccines; Public Workshop

Science.gov (United States)

2011-08-11

...] The Development and Evaluation of Next-Generation Smallpox Vaccines; Public Workshop AGENCY: Food and... Evaluation of Next-Generation Smallpox Vaccines.'' The purpose of the public workshop is to identify and discuss the key issues related to the development and evaluation of next-generation smallpox vaccines. The...

Vaccination against Salmonella Infection: the Mucosal Way.

Science.gov (United States)

Gayet, Rémi; Bioley, Gilles; Rochereau, Nicolas; Paul, Stéphane; Corthésy, Blaise

2017-09-01

Salmonella enterica subspecies enterica includes several serovars infecting both humans and other animals and leading to typhoid fever or gastroenteritis. The high prevalence of associated morbidity and mortality, together with an increased emergence of multidrug-resistant strains, is a current global health issue that has prompted the development of vaccination strategies that confer protection against most serovars. Currently available systemic vaccine approaches have major limitations, including a reduced effectiveness in young children and a lack of cross-protection among different strains. Having studied host-pathogen interactions, microbiologists and immunologists argue in favor of topical gastrointestinal administration for improvement in vaccine efficacy. Here, recent advances in this field are summarized, including mechanisms of bacterial uptake at the intestinal epithelium, the assessment of protective host immunity, and improved animal models that closely mimic infection in humans. The pros and cons of existing vaccines are presented, along with recent progress made with novel formulations. Finally, new candidate antigens and their relevance in the refined design of anti- Salmonella vaccines are discussed, along with antigen vectorization strategies such as nanoparticles or secretory immunoglobulins, with a focus on potentiating mucosal vaccine efficacy. Copyright © 2017 American Society for Microbiology.

Preclinical development of a vaccine 'against smoking'.

Science.gov (United States)

Cerny, E H; Lévy, R; Mauel, J; Mpandi, M; Mutter, M; Henzelin-Nkubana, C; Patiny, L; Tuchscherer, G; Cerny, T

2002-10-01

Nicotine is the main culprit for dependence on tobacco-containing products, which in turn are a major etiologic factor for cardiovascular diseases and cancer. This publication describes a vaccine, which elicits antibodies against nicotine. The antibodies in the blood stream intercept the nicotine molecule on its way to its receptors and greatly diminish the nicotine influx to the brain shortly after smoking. The nicotine molecule is chemically linked to cholera toxin B as a carrier protein in order to induce antibodies. The potential to elicit antibodies after subcutaneous as well as intranasal immunization is evaluated. In order to simulate realistic conditions, nicotine pumps delivering the nicotine equivalent of 5 packages of cigarettes for 4 weeks are implanted into the mice 1 week prior to vaccination. The protective effect of the vaccine is measured 5 weeks after vaccination by comparing the influx of radiolabeled nicotine in the brains of vaccinated and non-vaccinated animals 5 min after challenge with the nicotine equivalent of 2 cigarettes. The polyclonal antibodies induced by the vaccine show a mean avidity of 1.8 x 10(7) l/Mol. Subcutaneous immunization elicits high antibody levels of the IgG class, and significant IgA antibody levels in the saliva of vaccinated mice can be found after intranasal vaccination. The protective effect also in the animals with implanted nicotine pumps is significant: less than 10% of radiolabeled nicotine found in the brains of non-vaccinated animals can be found in the brains of vaccinated animals. These data provide credible evidence that a vaccine can break the vicious circle between smoking and instant gratification by intercepting the nicotine molecule. Astonishingly, there is no sign of exhaustion of specific antibodies even under extreme conditions, which makes it highly unlikely that a smoker can overcome the protective effect of the vaccine by smoking more. Finally, the high titers of specific antibodies after 1 year

Recent advances in vaccine development for herpes simplex virus types I and II.

Science.gov (United States)

Coleman, Jeffrey L; Shukla, Deepak

2013-04-01

Despite recent advances in vaccine design and strategies, latent infection with herpes simplex virus (HSV) remains a formidable challenge. Approaches involving live-attenuated viruses and inactivated viral preparations were popular throughout the twentieth century. In the past ten years, many vaccine types, both prophylactic or therapeutic, have contained a replication-defective HSV, viral DNA or glycoproteins. New research focused on the mechanism of immune evasion by the virus has involved developing vaccines with various gene deletions and manipulations combined with the use of new and more specific adjuvants. In addition, new "prime-boost" methods of strengthening the vaccine efficacy have proven effective, but there have also been flaws with some recent strategies that appear to have compromised vaccine efficacy in humans. Given the complicated lifecycle of HSV and its unique way of spreading from cell-to-cell, it can be concluded that the development of an ideal vaccine needs new focus on cell-mediated immunity, better understanding of the latent viral genome and serious consideration of gender-based differences in immunity development among humans. This review summarizes recent developments made in the field and sheds light on some potentially new ways to conquer the problem including development of dual-action prophylactic microbicides that prohibit viral entry and, in addition, induce a strong antigen response.

Novel adjuvants & delivery vehicles for vaccines development: a road ahead.

Science.gov (United States)

Mohan, Teena; Verma, Priyanka; Rao, D Nageswara

2013-11-01

The pure recombinant and synthetic antigens used in modern day vaccines are generally less immunogenic than older style live/attenuated and killed whole organism vaccines. One can improve the quality of vaccine production by incorporating immunomodulators or adjuvants with modified delivery vehicles viz. liposomes, immune stimulating complexes (ISCOMs), micro/nanospheres apart from alum, being used as gold standard. Adjuvants are used to augment the effect of a vaccine by stimulating the immune system to respond to the vaccine, more vigorously, and thus providing increased immunity to a particular disease. Adjuvants accomplish this task by mimicking specific sets of evolutionary conserved molecules which include lipopolysaccharides (LPS), components of bacterial cell wall, endocytosed nucleic acids such as dsRNA, ssDNA and unmethylated CpG dinucleotide containing DNA. This review provides information on various vaccine adjuvants and delivery vehicles being developed to date. From literature, it seems that the humoral immune responses have been observed for most adjuvants and delivery platforms while viral-vector, ISCOMs and Montanides have shown cytotoxic T-cell response in the clinical trials. MF59 and MPL® have elicited Th1 responses, and virus-like particles (VLPs), non-degradable nanoparticle and liposomes have also generated cellular immunity. Such vaccine components have also been evaluated for alternative routes of administration with clinical success reported for intranasal delivery of viral-vectors and proteosomes and oral delivery of VLP vaccines.

Mycobacterium tuberculosis: approach to development of improved strategies for disease control through vaccination and immunodiagnosis.

Science.gov (United States)

Mirlekar, B; Pathak, S; Pathade, G

2013-01-01

Tuberculosis is a major health problem throughout the world causing large number of deaths, more than that from any other single infectious disease. Estimates till date ascertain the fact that Tuberculosis (TB) is continuing to be the leading cause of death worldwide. The infection from single infectious agent Mycobacterium tuberculosis is killing about 3 million individuals every year and accounts for around 18.5% of all deaths in adults between the age group of 15 and 65. An average of 1.79 billion people, which constitutes roughly one-third of the world's population, is infected with the causative agent M. tuberculosis and is at risk of developing the disease. This situation highlights the relative shortcomings of the current treatment and diagnosis strategies for TB and the limited effectiveness of public health systems, particularly in resource-poor countries where the main TB burden lies. The timely identification of persons infected with Mycobacterium tuberculosis and rapid laboratory confirmation of tuberculosis are two key factors for the treatment and prevention of the disease. Novel molecular assays for diagnosis and drug susceptibility testing offer several potential advantages over the above methods including faster turnaround times, very sensitive and specific detection of nucleic acids, and minimal, or possibly no, prior culture. The need for new technologies for rapid diagnosis of tuberculosis is clear. Most studies of mycobacterial immunity attributes focus on proliferation of T cells, production of cytokines and cytolytic activity. A proper vaccine for tuberculosis can be developed by using a combination of antigens and adjuvants capable of inducing appropriate and long-lasting T cell immunity. Development of new vaccines against TB should include some important aspects learned from BCG use such as mucosal routes of immunization; revaccination of BCG immunized subjects, booster immunization and prime-boost strategy with wild-type BCG, and other

A New Scientific Paradigm may be Needed to Finally Develop an HIV Vaccine.

Science.gov (United States)

Esparza, José

2015-01-01

The bulk of current HIV vaccine research is conducted within the infectious disease paradigm that has been very successful in developing vaccines against many other viral diseases. Different HIV vaccine concepts, based on the induction of neutralizing antibodies and/or cell mediated immunity, have been developed and clinically tested over the last 30 years, resulting in a few small successes and many disappointments. As new scientific knowledge is obtained, HIV vaccine concepts are constantly modified with the hope that the newly introduced tweaks (or paradigm drifts) will provide the solution to one of the most difficult challenges that modern biomedical research is confronting. Efficacy trials have been critical in guiding HIV vaccine development. However, from the five phase III efficacy trials conducted to date, only one (RV144) resulted in modest efficacy. The results from RV144 were surprising in many ways, including the identified putative correlates of protection (or risk), which did not include neutralizing antibodies or cytotoxic T-cells. The solution to the HIV vaccine challenge may very well come from approaches based on the current paradigm. However, at the same time, out-of-the-paradigm ideas should be systematically explored to complement the current efforts. New mechanisms are needed to identify and support the innovative research that will hopefully accelerate the development of an urgently needed HIV vaccine.

Correlates of Protection for M Protein-Based Vaccines against Group A Streptococcus

Directory of Open Access Journals (Sweden)

Shu Ki Tsoi

2015-01-01

Full Text Available Group A streptococcus (GAS is known to cause a broad spectrum of illness, from pharyngitis and impetigo, to autoimmune sequelae such as rheumatic heart disease, and invasive diseases. It is a significant cause of infectious disease morbidity and mortality worldwide, but no efficacious vaccine is currently available. Progress in GAS vaccine development has been hindered by a number of obstacles, including a lack of standardization in immunoassays and the need to define human correlates of protection. In this review, we have examined the current immunoassays used in both GAS and other organisms, and explored the various challenges in their implementation in order to propose potential future directions to identify a correlate of protection and facilitate the development of M protein-based vaccines, which are currently the main GAS vaccine candidates.

Correlates of Protection for M Protein-Based Vaccines against Group A Streptococcus

Science.gov (United States)

Smeesters, Pierre R.; Frost, Hannah R. C.; Steer, Andrew C.

2015-01-01

Group A streptococcus (GAS) is known to cause a broad spectrum of illness, from pharyngitis and impetigo, to autoimmune sequelae such as rheumatic heart disease, and invasive diseases. It is a significant cause of infectious disease morbidity and mortality worldwide, but no efficacious vaccine is currently available. Progress in GAS vaccine development has been hindered by a number of obstacles, including a lack of standardization in immunoassays and the need to define human correlates of protection. In this review, we have examined the current immunoassays used in both GAS and other organisms, and explored the various challenges in their implementation in order to propose potential future directions to identify a correlate of protection and facilitate the development of M protein-based vaccines, which are currently the main GAS vaccine candidates. PMID:26101780

Progress of dendritic cell-based cancer vaccines for patients with hematological malignancies.

Science.gov (United States)

Ni, Ming; Hoffmann, Jean-Marc; Schmitt, Michael; Schmitt, Anita

2016-09-01

Dendritic cells (DCs) are the most professional antigen-presenting cells eliciting cellular and humoral immune responses against cancer cells by expressing these antigens on MHC class I/II complexes to T cells. Therefore, they have been employed in many clinical trials as cancer vaccines for patients with cancer. This review focuses on the use of DCs in leukemia patients expressing leukemia-associated antigens (LAAs). The contribution of both stimulating vs. tolerogenic DCs as well as of other factors to the milieu of anti-leukemia immune responses are discussed. Several DC vaccination strategies like leukemia lysate, proteins and peptides have been developed. Next generation DC vaccines comprise transduction of DCs with retroviral vectors encoding for LAAs, cytokines and costimulatory molecules as well as transfection of DCs with naked RNA encoding for LAAs. Published as well as ongoing clinical trials are reported and critically reviewed. Future results will demonstrate whether next-generation DCs are really superior to conventional pulsing with peptide, protein or tumor lysate. However, currently available methods based on nucleic acid transfection/transduction are tempting in terms of material production costs and time for clinical application according to good manufacturing practice (GMP).

Developing Universal Influenza Vaccines: Hitting the Nail, Not Just on the Head

Directory of Open Access Journals (Sweden)

Lidewij C. M. Wiersma

2015-03-01

Full Text Available Influenza viruses have a huge impact on public health. Current influenza vaccines need to be updated annually and protect poorly against antigenic drift variants or novel emerging subtypes. Vaccination against influenza can be improved in two important ways, either by inducing more broadly protective immune responses or by decreasing the time of vaccine production, which is relevant especially during a pandemic outbreak. In this review, we outline the current efforts to develop so-called “universal influenza vaccines”, describing antigens that may induce broadly protective immunity and novel vaccine production platforms that facilitate timely availability of vaccines.

Applying Mathematical Tools to Accelerate Vaccine Development: Modeling Shigella Immune Dynamics

Science.gov (United States)

Davis, Courtney L.; Wahid, Rezwanul; Toapanta, Franklin R.; Simon, Jakub K.

2013-01-01

We establish a mathematical framework for studying immune interactions with Shigella, a bacteria that kills over one million people worldwide every year. The long-term goal of this novel approach is to inform Shigella vaccine design by elucidating which immune components and bacterial targets are crucial for establishing Shigella immunity. Our delay differential equation model focuses on antibody and B cell responses directed against antigens like lipopolysaccharide in Shigella’s outer membrane. We find that antibody-based vaccines targeting only surface antigens cannot elicit sufficient immunity for protection. Additional boosting prior to infection would require a four-orders-of-magnitude increase in antibodies to sufficiently prevent epithelial invasion. However, boosting anti-LPS B memory can confer protection, which suggests these cells may correlate with immunity. We see that IgA antibodies are slightly more effective per molecule than IgG, but more total IgA is required due to spatial functionality. An extension of the model reveals that targeting both LPS and epithelial entry proteins is a promising avenue to advance vaccine development. This paper underscores the importance of multifaceted immune targeting in creating an effective Shigella vaccine. It introduces mathematical models to the Shigella vaccine development effort and lays a foundation for joint theoretical/experimental/clinical approaches to Shigella vaccine design. PMID:23589755

Adaptive Immunity to Francisella tularensis and Considerations for Vaccine Development

Directory of Open Access Journals (Sweden)

Lydia M. Roberts

2018-04-01

Full Text Available Francisella tularensis is an intracellular bacterium that causes the disease tularemia. There are several subspecies of F. tularensis whose ability to cause disease varies in humans. The most virulent subspecies, tularensis, is a Tier One Select Agent and a potential bioweapon. Although considerable effort has made to generate efficacious tularemia vaccines, to date none have been licensed for use in the United States. Despite the lack of a tularemia vaccine, we have learned a great deal about the adaptive immune response the underlies protective immunity. Herein, we detail the animal models commonly used to study tularemia and their recapitulation of human disease, the field's current understanding of vaccine-mediated protection, and discuss the challenges associated with new vaccine development.

The Feasibility of Gamma Irradiation for Developing Malaria Vaccine

International Nuclear Information System (INIS)

Syaifudin, M.; Tetriana, D.; Darlina; Nurhayati, S.

2011-01-01

Malaria, a plasmodial disease, causes more than one million deaths per year and has a significant public health impact. Improved access to prompt treatment with effective antimalarial drugs need to be conducted for prevention of infection in high risk groups. However, the parasite as causal agent has exhibited a potential danger of wide-spread resistances. This warning has directed attention to the study of alternative methods of protection against the disease, among them is to do the immunization. A deeper understanding of the nature and regulation of protective immune mechanisms against this parasite will facilitate the development of much needed vaccines. Developing a malaria vaccine remains an enormous scientific, technical, and financial challenge. Currently a vaccine is not fully available. Among the practical applications of radiobiological techniques that may be of considerable interest for public health is the use of ionizing radiation in the preparation of vaccines. Convincing data were reported that sporozoites of Plasmodium berghei irradiated with X- or gamma-rays, provide an antigenic stimulus effective to induce a protective immune response in mice and rats against subsequent sporozoite infection. Irradiated parasites are better immunogens than killed ones and although non-infective they are still metabolically active, as shown by continued protein and nucleic acid synthesis. There is a substantial number of data from human studies demonstrating that sporozoites attenuated by radiation are potent inducer of protective immunity and that they are safe and do not give rise to the asexual erythrocytic infections that cause malaria. This vaccine is relatively inexpensive to produce, easy to store, and transportable without refrigeration. A long-term effort and commitment to providing resources must be maintained and increased to achieve the goal of a malaria vaccine candidate where ionizing radiation as a tool to prepare is seemingly feasible. (author)

Stakeholders' perceptions of 10years of the Global Action Plan for Influenza Vaccines (GAP) - Results from a survey.

Science.gov (United States)

Nannei, Claudia; Goldin, Shoshanna; Torelli, Guido; Fatima, Hiba; Kumar, Kaveri; Bubb-Humfryes, Oliver; Stenson, Bo; Sparrow, Erin

2016-10-26

Ten years after the launch of the Global Action Plan for Influenza Vaccines (GAP), the World Health Organization (WHO) surveyed stakeholders to understand their perceptions of what the programme had achieved. This article provides a summary of the findings; the full report will be available on-line on the GAP website in November 2016 (http://www.who.int/influenza_vaccines_plan/en/). Seventy-seven responses were received from stakeholders including medical doctors, national influenza center officials, country immunization programme teams, surveillance and disease centers, policy-makers, researchers, vaccine manufacturers, and non-governmental organizations from 28 countries, representing all six WHO regions. Respondents cited GAP's biggest successes as capacity building in developing countries; raising international awareness of global needs in the event of a pandemic; and collaborative alignment of influenza stakeholders. The most commonly reported challenges were the limited progress in development of a broadly protective or universal vaccine and the perceived absence of a major increase in seasonal demand. These findings aligned with the perception that less global progress had been made under the third GAP objective, focused on research and development of better vaccines, than on increasing seasonal vaccine use (objective 1) and pandemic vaccine production capacity (objective 2). Respondents explained what they saw as the major challenges to development of better vaccines, including to development of a universal influenza vaccine. The majority of respondents agreed that the goal chosen at the GAP II consultation is still relevant. Results highlighted the importance of promoting research and development of better vaccines, both for facilitating uptake of seasonal vaccines and for ensuring timely vaccine availability in the event of a pandemic. As the GAP concludes its mandate this year, these findings will contribute to discussions on the impact of programme

Adenovirus-vectored Ebola vaccines.

Science.gov (United States)

Gilbert, Sarah C

2015-01-01

The 2014 outbreak of Ebola virus disease in West Africa has highlighted the need for the availability of effective vaccines against outbreak pathogens that are suitable for use in frontline workers who risk their own health in the course of caring for those with the disease, and also for members of the community in the affected area. Along with effective contact tracing and quarantine, use of a vaccine as soon as an outbreak is identified could greatly facilitate rapid control and prevent the outbreak from spreading. This review describes the progress that has been made in producing and testing adenovirus-based Ebola vaccines in both pre-clinical and clinical studies, and considers the likely future use of these vaccines.

Vaccines against poverty

Science.gov (United States)

MacLennan, Calman A.; Saul, Allan

2014-01-01

With the 2010s declared the Decade of Vaccines, and Millennium Development Goals 4 and 5 focused on reducing diseases that are potentially vaccine preventable, now is an exciting time for vaccines against poverty, that is, vaccines against diseases that disproportionately affect low- and middle-income countries (LMICs). The Global Burden of Disease Study 2010 has helped better understand which vaccines are most needed. In 2012, US$1.3 billion was spent on research and development for new vaccines for neglected infectious diseases. However, the majority of this went to three diseases: HIV/AIDS, malaria, and tuberculosis, and not neglected diseases. Much of it went to basic research rather than development, with an ongoing decline in funding for product development partnerships. Further investment in vaccines against diarrheal diseases, hepatitis C, and group A Streptococcus could lead to a major health impact in LMICs, along with vaccines to prevent sepsis, particularly among mothers and neonates. The Advanced Market Commitment strategy of the Global Alliance for Vaccines and Immunisation (GAVI) Alliance is helping to implement vaccines against rotavirus and pneumococcus in LMICs, and the roll out of the MenAfriVac meningococcal A vaccine in the African Meningitis Belt represents a paradigm shift in vaccines against poverty: the development of a vaccine primarily targeted at LMICs. Global health vaccine institutes and increasing capacity of vaccine manufacturers in emerging economies are helping drive forward new vaccines for LMICs. Above all, partnership is needed between those developing and manufacturing LMIC vaccines and the scientists, health care professionals, and policy makers in LMICs where such vaccines will be implemented. PMID:25136089

Clinical trials for vaccine development in registry of Korea Food and Drug Administration.

Science.gov (United States)

Kang, Seog-Youn

2013-01-01

Based on the action plan "Ensuring a stable supply of National Immunization Program vaccines and sovereignty of biopharmaceutical products," Korea Food and Drug Administration (KFDA) has made efforts to develop vaccines in the context of self reliance and to protect public health. Along with the recognized infrastructures for clinical trials, clinical trials for vaccines have also gradually been conducted at multinational sites as well as at local sites. KFDA will support to expand six to eleven kinds of vaccines by 2017. In accordance with integrated regulatory system, KFDA has promoted clinical trials, established national lot release procedure, and strengthened good manufacturing practices inspection and post marketing surveillance. Against this backdrop, KFDA will support the vaccine development and promote excellent public health protection.

Exosomes Enter Vaccine Development: Strategies Meeting Global Challenges of Emerging Infections.

Science.gov (United States)

Jungbauer, Alois

2018-04-01

New approaches for vaccination must be developed in order to meet the grand challenges for emerging infectious diseases. Exosomes now enter vaccine development and these are strategies are meeting these global challenges, as demonstrated by Anticoli et al., in this issue of Biotechnology Journal. Using exosome vaccines has been now been demonstrated in vivo for several viruses such as Ebola Virus VP24, VP40, and NP, Influenza Virus NP, Crimean-Congo Hemorrhagic Fever NP, West Nile Virus NS3, and Hepatitis C Virus NS3. Now this technology must be tested in clinics. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Terapeutiske vacciner er et nyt behandlings-princip ved kastrationsresistent prostatacancer

DEFF Research Database (Denmark)

Djurhuus, Sissal Sigmundsdòttir; Brasso, Klaus; Berg, Kasper Drimer

2015-01-01

Therapeutic vaccines is a novel approach in castration-resistant prostate cancer treatment Castration-resistant prostate cancer (CRPC) is defined as tumour progression despite castrate levels of serum testosterone. During the past decade a number of new therapies, including chemo­therapy and novel...... endocrine agents have been approved for CRPC treatment. The continued need for new effective drugs in CRPC has led to development of a novel therapeutic approach in CRPC treatment. Therapeutic vaccines activate the immune system to kill prostate cancer cells. This review describes recent pivotal phase 2...... and 3 trials of CRPC vaccines and discusses the impact on future CRPC management....

Progression of rabbit haemorrhagic disease virus 2 upon vaccination in an industrial rabbitry: a laboratorial approach

Directory of Open Access Journals (Sweden)

C.L. Carvalho

2017-03-01

Full Text Available Rabbit haemorrhagic disease virus 2 (RHDV2 emerged recently in several European countries, leading to extensive economic losses in the industry. In response to this new infection, specific inactivated vaccines were developed in Europe and full and rapid setup of protective immunity induced by vaccination was reported. However, data on the efficacy of these vaccines in an ongoing-infection scenario is unavailable. In this study we investigated an infected RHDV2 indoor industrial meat rabbitry, where fatalities continued to occur after the implementation of the RHDV2 vaccination, introduced to control the disease. The aim of this study was to understand if these mortalities were RHDV2-related, to discover if the dead animals showed any common features such as age or time distance from vaccination, and to identify the source of the outbreak. Anatomo-pathological analysis of vaccinated animals with the virus showed lesions compatible with systemic haemorrhagic disease and RHDV2-RNA was detected in 85.7% of the animals tested. Sequencing of the vp60 gene amplified from liver samples led to the recognition of RHDV2 field strains demonstrating that after the implementation of vaccination, RHDV2 continued to circulate in the premises and to cause sporadic deaths. A nearby, semi-intensive, RHDV2 infected farm belonging to the same owner was identified as the most probable source of the virus. The main risk factors for virus introduction in these two industries were identified. Despite the virus being able to infect a few of the vaccinated rabbits, the significant decrease in mortality rate observed in vaccinated adult rabbits clearly reflects the efficacy of the vaccination. Nonetheless, the time taken to control the infection also highlights the importance of RHDV2 vaccination prior to the first contact with the virus, highly recommendable in endemic areas, to mitigate the infection’s impact on the industry.

Strengthening vaccination policies in Latin America: an evidence-based approach.

Science.gov (United States)

Tapia-Conyer, Roberto; Betancourt-Cravioto, Miguel; Saucedo-Martínez, Rodrigo; Motta-Murguía, Lourdes; Gallardo-Rincón, Héctor

2013-08-20

Despite many successes in the region, Latin American vaccination policies have significant shortcomings, and further work is needed to maintain progress and prepare for the introduction of newly available vaccines. In order to address the challenges facing Latin America, the Commission for the Future of Vaccines in Latin America (COFVAL) has made recommendations for strengthening evidence-based policy-making and reducing regional inequalities in immunisation. We have conducted a comprehensive literature review to assess the feasibility of these recommendations. Standardisation of performance indicators for disease burden, vaccine coverage, epidemiological surveillance and national health resourcing can ensure comparability of the data used to assess vaccination programmes, allowing deeper analysis of how best to provide services. Regional vaccination reference schemes, as used in Europe, can be used to develop best practice models for vaccine introduction and scheduling. Successful models exist for the continuous training of vaccination providers and decision-makers, with a new Latin American diploma aiming to contribute to the successful implementation of vaccination programmes. Permanent, independent vaccine advisory committees, based on the US Advisory Committee on Immunization Practices (ACIP), could facilitate the uptake of new vaccines and support evidence-based decision-making in the administration of national immunisation programmes. Innovative financing mechanisms for the purchase of new vaccines, such as advance market commitments and cost front-loading, have shown potential for improving vaccine coverage. A common regulatory framework for vaccine approval is needed to accelerate delivery and pool human, technological and scientific resources in the region. Finally, public-private partnerships between industry, government, academia and non-profit sectors could provide new investment to stimulate vaccine development in the region, reducing prices in the

Review Article: Vaccine for Malaria – How Far? | Oyeyinka | African ...

African Journals Online (AJOL)

This is a review of the progress made so far in the effort to produce a malaria vaccine. The problems that have made it impossible to get an effective vaccine for malaria are discussed. Also examined are the current efforts to produce the vaccine and the prospects for an effective vaccine in the future. Key words: Vaccine ...

Vaccines today, vaccines tomorrow: a perspective.

Science.gov (United States)

Loucq, Christian

2013-01-01

Vaccines are considered as one of the major contributions of the 20th century and one of the most cost effective public health interventions. The International Vaccine Institute has as a mission to discover, develop and deliver new and improved vaccines against infectious diseases that affects developing nations. If Louis Pasteur is known across the globe, vaccinologists like Maurice Hilleman, Jonas Salk and Charles Mérieux are known among experts only despite their contribution to global health. Thanks to a vaccine, smallpox has been eradicated, polio has nearly disappeared, Haemophilus influenzae B, measles and more recently meningitis A are controlled in many countries. While a malaria vaccine is undergoing phase 3, International Vaccine Institute, in collaboration with an Indian manufacturer has brought an oral inactivated cholera vaccine to pre-qualification. The field of vaccinology has undergone major changes thanks to philanthropists such as Bill and Melinda Gates, initiatives like the Decade of Vaccines and public private partnerships. Current researches on vaccines have more challenging targets like the dengue viruses, malaria, human immunodeficiency virus, the respiratory syncytial virus and nosocomial diseases. Exciting research is taking place on new adjuvants, nanoparticles, virus like particles and new route of administration. An overcrowded infant immunization program, anti-vaccine groups, immunizing a growing number of elderlies and delivering vaccines to difficult places are among challenges faced by vaccinologists and global health experts.

Enhancing the role of veterinary vaccines reducing zoonotic diseases of humans: Linking systems biology with vaccine development

Energy Technology Data Exchange (ETDEWEB)

Adams, Leslie G.; Khare, Sangeeta; Lawhon, Sara D.; Rossetti, Carlos A.; Lewin, Harris A.; Lipton, Mary S.; Turse, Joshua E.; Wylie, Dennis C.; Bai, Yu; Drake, Kenneth L.

2011-09-22

The aim of research on infectious diseases is their prevention, and brucellosis and salmonellosis as such are classic examples of worldwide zoonoses for application of a systems biology approach for enhanced rational vaccine development. When used optimally, vaccines prevent disease manifestations, reduce transmission of disease, decrease the need for pharmaceutical intervention, and improve the health and welfare of animals, as well as indirectly protecting against zoonotic diseases of people. Advances in the last decade or so using comprehensive systems biology approaches linking genomics, proteomics, bioinformatics, and biotechnology with immunology, pathogenesis and vaccine formulation and delivery are expected to enable enhanced approaches to vaccine development. The goal of this paper is to evaluate the role of computational systems biology analysis of host:pathogen interactions (the interactome) as a tool for enhanced rational design of vaccines. Systems biology is bringing a new, more robust approach to veterinary vaccine design based upon a deeper understanding of the host pathogen interactions and its impact on the host's molecular network of the immune system. A computational systems biology method was utilized to create interactome models of the host responses to Brucella melitensis (BMEL), Mycobacterium avium paratuberculosis (MAP), Salmonella enterica Typhimurium (STM), and a Salmonella mutant (isogenic *sipA, sopABDE2) and linked to the basis for rational development of vaccines for brucellosis and salmonellosis as reviewed by Adams et al. and Ficht et al. [1,2]. A bovine ligated ileal loop biological model was established to capture the host gene expression response at multiple time points post infection. New methods based on Dynamic Bayesian Network (DBN) machine learning were employed to conduct a comparative pathogenicity analysis of 219 signaling and metabolic pathways and 1620 gene ontology (GO) categories that defined the host

Rotavirus vaccines and vaccination in Latin America

Directory of Open Access Journals (Sweden)

Linhares Alexandre C.

2000-01-01

Full Text Available Worldwide, rotaviruses account for more than 125 million cases of infantile gastroenteritis and nearly 1 million deaths per year, mainly in developing countries. Rather than other control measures, vaccination is most likely to have a major impact on rotavirus disease incidence. The peak incidence of rotavirus diarrhea occurs between 6 and 24 months of age. In developing countries, however, cases are not uncommon among children younger than 6 months. G serotypes 1 to 4 are responsible for most disease, but there are indications that in Brazil that G type 5 is of emerging epidemiological importance. Both homotypic and heterotypic responses are elicited during natural rotavirus infection, and the immunological response at the intestinal mucosal surface is probably the more consistent predictor of clinical immunity. With the primary objective of protecting children against life-threatening dehydrating diarrhea, many approaches to rotavirus vaccine development have been attempted. One vaccine, the tetravalent rhesus-human reassortant rotavirus vaccine (RRV-TV, was given licensing approval in the United States of America, introduced to the market, and later withdrawn. A number of studies have found better efficacy of RRV-TV in developed countries than in developing ones. Field trials with a 4 X 10(4 plaque-forming units (PFU preparation of RRV-TV have been carried out in two countries in Latin America, Brazil and Peru. Those trials yielded protective efficacy rates against all rotavirus diarrhea ranging from 18% to 35%. Data from a large catchment trial in Venezuela with a higher RRV-TV dose, of 4 X 10(5 PFU/dose, indicated an efficacy rate of 48% against all rotavirus diarrhea and 88% against severe rotavirus diarrhea. It appears that breast-feeding does not compromise the efficacy of RRV-TV if three doses of the vaccine are administered. Similarly, possible interference of oral poliovirus vaccine with the "take" of the rotavirus vaccine can be

Rotavirus vaccines and vaccination in Latin America

Directory of Open Access Journals (Sweden)

Alexandre C. Linhares

2000-11-01

Full Text Available Worldwide, rotaviruses account for more than 125 million cases of infantile gastroenteritis and nearly 1 million deaths per year, mainly in developing countries. Rather than other control measures, vaccination is most likely to have a major impact on rotavirus disease incidence. The peak incidence of rotavirus diarrhea occurs between 6 and 24 months of age. In developing countries, however, cases are not uncommon among children younger than 6 months. G serotypes 1 to 4 are responsible for most disease, but there are indications that in Brazil that G type 5 is of emerging epidemiological importance. Both homotypic and heterotypic responses are elicited during natural rotavirus infection, and the immunological response at the intestinal mucosal surface is probably the more consistent predictor of clinical immunity. With the primary objective of protecting children against life-threatening dehydrating diarrhea, many approaches to rotavirus vaccine development have been attempted. One vaccine, the tetravalent rhesus-human reassortant rotavirus vaccine (RRV-TV, was given licensing approval in the United States of America, introduced to the market, and later withdrawn. A number of studies have found better efficacy of RRV-TV in developed countries than in developing ones. Field trials with a 4 X 10(4 plaque-forming units (PFU preparation of RRV-TV have been carried out in two countries in Latin America, Brazil and Peru. Those trials yielded protective efficacy rates against all rotavirus diarrhea ranging from 18% to 35%. Data from a large catchment trial in Venezuela with a higher RRV-TV dose, of 4 X 10(5 PFU/dose, indicated an efficacy rate of 48% against all rotavirus diarrhea and 88% against severe rotavirus diarrhea. It appears that breast-feeding does not compromise the efficacy of RRV-TV if three doses of the vaccine are administered. Similarly, possible interference of oral poliovirus vaccine with the "take" of the rotavirus vaccine can be

Longitudinal myelitis associated with yellow fever vaccination.

Science.gov (United States)

Chaves, M; Riccio, P; Patrucco, L; Rojas, J I; Cristiano, E

2009-07-01

Severe adverse reaction to yellow fever (YF) vaccine includes the yellow fever vaccine-associated neurotropic disease. This terminology includes postvaccinal encephalitis, acute disseminated encephalomyelitis, and Guillain-Barré syndrome. The objective of this communication is to report a patient who received a YF vaccine in Argentina and subsequently developed longitudinal myelitis with a symptom that had previously gone unreported in the literature. A 56-year-old man began with progressive paraparesia, urinary retention, and constipation 48 h previous to admission. The patient received YF vaccine 45 days prior to the onset of the symptoms. There was no history of other immunization or relevant condition. MR of the spine showed longitudinal intramedullary hyperintense signal (D5-12) without gadolinium enhancement. A high concentration of YFV-specific IgM vaccine antibody was found in the cerebrospinal fluid (CSF). Serological tests for other flavivirus were negative. A diagnosis of longitudinal myelitis without encephalitis associated with YF vaccine was performed and symptoms improved 5 days later. This is the first report dealing with longitudinal myelitis as a serious adverse event associated with YF vaccination in which confirmation of the presence of antibodies in CSF was found. To date, it is also the first report with serological confirmation in Argentina and in South America. We consider that the present investigation will raise awareness in the region in the reporting of adverse events related to YF vaccine and improve our knowledge of adverse reactions to the vaccine.

Malaria vaccines and their potential role in the elimination of malaria

Directory of Open Access Journals (Sweden)

Greenwood Brian M

2008-12-01

Full Text Available Abstract Research on malaria vaccines is currently directed primarily towards the development of vaccines that prevent clinical malaria. Malaria elimination, now being considered seriously in some epidemiological situations, requires a different vaccine strategy, since success will depend on killing all parasites in the community in order to stop transmission completely. The feature of the life-cycles of human malarias that presents the greatest challenge to an elimination programme is the persistence of parasites as asymptomatic infections. These are an important source from which transmission to mosquitoes can occur. Consequently, an elimination strategy requires a community-based approach covering all individuals and not just those who are susceptible to clinical malaria. The progress that has been made in development of candidate malaria vaccines is reviewed. It is unlikely that many of these will have the efficacy required for complete elimination of parasites, though they may have an important role to play as part of future integrated control programmes. Vaccines for elimination must have a high level of efficacy in order to stop transmission to mosquitoes. This might be achieved with some pre-erythrocytic stage candidate vaccines or by targeting the sexual stages directly with transmission-blocking vaccines. An expanded malaria vaccine programme with such objectives is now a priority.

Controlled human infection models for vaccine development: Zika virus debate.

Science.gov (United States)

Gopichandran, Vijayaprasad

2018-01-01

An ethics panel, convened by the National Institute of Health and other research bodies in the USA, disallowed researchers from the Johns Hopkins University and University of Vermont from performing controlled human infection of healthy volunteers to develop a vaccine against Zika virus infection. The members published their ethical analysis and recommendations in February 2017. They have elaborated on the risks posed by human challenge with Zika virus to the volunteers and other uninvolved third parties and have systematically analysed the social value of such a human challenge experiment. They have also posited some mandatory ethical requirements which should be met before allowing the infection of healthy volunteers with the Zika virus. This commentary elaborates on the debate on the ethics of the human challenge model for the development of a Zika virus vaccine and the role of systematic ethical analysis in protecting the interests of research participants. It further analyses the importance of this debate to the development of a Zika vaccine in India.

Identifying optimal vaccination strategies for serogroup A Neisseria meningitidis conjugate vaccine in the African meningitis belt.

Directory of Open Access Journals (Sweden)

Sara Tartof

Full Text Available The optimal long-term vaccination strategies to provide population-level protection against serogroup A Neisseria meningitidis (MenA are unknown. We developed an age-structured mathematical model of MenA transmission, colonization, and disease in the African meningitis belt, and used this model to explore the impact of various vaccination strategies.The model stratifies the simulated population into groups based on age, infection status, and MenA antibody levels. We defined the model parameters (such as birth and death rates, age-specific incidence rates, and age-specific duration of protection using published data and maximum likelihood estimation. We assessed the validity of the model by comparing simulated incidence of invasive MenA and prevalence of MenA carriage to observed incidence and carriage data.The model fit well to observed age- and season-specific prevalence of carriage (mean pseudo-R2 0.84 and incidence of invasive disease (mean R2 0.89. The model is able to reproduce the observed dynamics of MenA epidemics in the African meningitis belt, including seasonal increases in incidence, with large epidemics occurring every eight to twelve years. Following a mass vaccination campaign of all persons 1-29 years of age, the most effective modeled vaccination strategy is to conduct mass vaccination campaigns every 5 years for children 1-5 years of age. Less frequent campaigns covering broader age groups would also be effective, although somewhat less so. Introducing conjugate MenA vaccine into the EPI vaccination schedule at 9 months of age results in higher predicted incidence than periodic mass campaigns.We have developed the first mathematical model of MenA in Africa to incorporate age structures and progressively waning protection over time. Our model accurately reproduces key features of MenA epidemiology in the African meningitis belt. This model can help policy makers consider vaccine program effectiveness when determining the

Varicella zoster vaccines and their implications for development of HSV vaccines

International Nuclear Information System (INIS)

Gershon, Anne A.

2013-01-01

Live attenuated vaccines to prevent varicella and zoster have been available in the US for the past 17 years, with a resultant dramatic decrease in varicella incidence and a predicted future decrease in the incidence of zoster. The pathogenesis and immune responses to varicella zoster virus (VZV) as well as the safety and effectiveness of VZV vaccines are reviewed. The lack of sterilizing immunity provided by VZV vaccines has not prevented them from being safe and effective. Virological and pathological information concerning parallels and differences between VZV and herpes simplex virus (HSV) are highlighted. Although VZV and HSV are distinct pathogens, they appear to have similarities in target organs and immunity that provide an expectation of a high likelihood for the success of vaccination against HSV, and predicted to be similar to that of VZV.

Varicella zoster vaccines and their implications for development of HSV vaccines

Energy Technology Data Exchange (ETDEWEB)

Gershon, Anne A., E-mail: aag1@columbia.edu [Department of Pediatrics, Columbia University College of Physicians and Surgeons, 620W. 168th Street, NY, NY 10032 (United States)

2013-01-05

Live attenuated vaccines to prevent varicella and zoster have been available in the US for the past 17 years, with a resultant dramatic decrease in varicella incidence and a predicted future decrease in the incidence of zoster. The pathogenesis and immune responses to varicella zoster virus (VZV) as well as the safety and effectiveness of VZV vaccines are reviewed. The lack of sterilizing immunity provided by VZV vaccines has not prevented them from being safe and effective. Virological and pathological information concerning parallels and differences between VZV and herpes simplex virus (HSV) are highlighted. Although VZV and HSV are distinct pathogens, they appear to have similarities in target organs and immunity that provide an expectation of a high likelihood for the success of vaccination against HSV, and predicted to be similar to that of VZV.

Terapeutiske vacciner er et nyt behandlingsprincip ved kastrationsresistent prostatacancer

DEFF Research Database (Denmark)

Djurhuus, Sissal Sigmundsdóttir; Brasso, Klaus; Berg, Kasper Drimer

2015-01-01

Castration-resistant prostate cancer (CRPC) is defined as tumour progression despite castrate levels of serum testosterone. During the past decade a number of new therapies, including chemotherapy and novel endocrine agents have been approved for CRPC treatment. The continued need for new effective...... drugs in CRPC has led to development of a novel therapeutic approach in CRPC treatment. Therapeutic vaccines activate the immune system to kill prostate cancer cells. This review describes recent pivotal phase 2 and 3 trials of CRPC vaccines and discusses the impact on future CRPC management....

The Current Status of the Disease Caused by Enterovirus 71 Infections: Epidemiology, Pathogenesis, Molecular Epidemiology, and Vaccine Development

Science.gov (United States)

Chang, Ping-Chin; Chen, Shou-Chien; Chen, Kow-Tong

2016-01-01

Enterovirus 71 (EV71) infections have a major public health impact in the Asia-Pacific region. We reviewed the epidemiology, pathogenesis, and molecular epidemiology of EV71 infection as well as EV71 vaccine development. Previous studies were found using the search terms “enterovirus 71” and “epidemiology” or “pathogenesis” or “molecular epidemiology” or “vaccine” in Medline and PubMed. Articles that were not published in the English language, manuscripts without an abstract, and opinion articles were excluded from the review. The reported epidemiology of cases caused by EV71 infection varied from country to country; seasonal variations in incidence were observed. Most cases of EV71 infection that resulted in hospitalization for complications occurred in children less than five years old. The brainstem was the most likely major target of EV71 infection. The emergence of the EV71 epidemic in the Asia-Pacific region has been associated with the circulation of different genetic lineages (genotypes B3, B4, C1, C2, and C4) that appear to be undergoing rapid evolutionary changes. The relationship between the gene structure of the EV71 virus and the factors that ensure its survival, circulation, and evasion of immunity is still unknown. EV71 infection has emerged as an important global public health problem. Vaccine development, including the development of inactivated whole-virus live attenuated, subviral particles, and DNA vaccines, has been progressing. PMID:27618078

Vero cell technology for rapid development of inactivated whole virus vaccines for emerging viral diseases.

Science.gov (United States)

Barrett, P Noel; Terpening, Sara J; Snow, Doris; Cobb, Ronald R; Kistner, Otfried

2017-09-01

Rapid development and production of vaccines against emerging diseases requires well established, validated, robust technologies to allow industrial scale production and accelerated licensure of products. Areas covered: A versatile Vero cell platform has been developed and utilized to deliver a wide range of candidate and licensed vaccines against emerging viral diseases. This platform builds on the 35 years' experience and safety record with inactivated whole virus vaccines such as polio vaccine. The current platform has been optimized to include a novel double inactivation procedure in order to ensure a highly robust inactivation procedure for novel emerging viruses. The utility of this platform in rapidly developing inactivated whole virus vaccines against pandemic (-like) influenza viruses and other emerging viruses such as West Nile, Chikungunya, Ross River and SARS is reviewed. The potential of the platform for development of vaccines against other emerging viruses such as Zika virus is described. Expert commentary: Use of this platform can substantially accelerate process development and facilitate licensure because of the substantial existing data set available for the cell matrix. However, programs to provide vaccines against emerging diseases must allow alternative clinical development paths to licensure, without the requirement to carry out large scale field efficacy studies.

Estimating the full public health value of vaccination.

Science.gov (United States)

Gessner, Bradford D; Kaslow, David; Louis, Jacques; Neuzil, Kathleen; O'Brien, Katherine L; Picot, Valentina; Pang, Tikki; Parashar, Umesh D; Saadatian-Elahi, Mitra; Nelson, Christopher B

2017-11-01

There is an enhanced focus on considering the full public health value (FPHV) of vaccination when setting priorities, making regulatory decisions and establishing implementation policy for public health activities. Historically, a therapeutic paradigm has been applied to the evaluation of prophylactic vaccines and focuses on an individual benefit-risk assessment in prospective and individually-randomized phase III trials to assess safety and efficacy against etiologically-confirmed clinical outcomes. By contrast, a public health paradigm considers the population impact and encompasses measures of community benefits against a range of outcomes. For example, measurement of the FPHV of vaccination may incorporate health inequity, social and political disruption, disruption of household integrity, school absenteeism and work loss, health care utilization, long-term/on-going disability, the development of antibiotic resistance, and a range of non-etiologically and etiologically defined clinical outcomes. Following an initial conference at the Fondation Mérieux in mid-2015, a second conference (December 2016) was held to further describe the efficacy of using the FPHV of vaccination on a variety of prophylactic vaccines. The wider scope of vaccine benefits, improvement in risk assessment, and the need for partnership and coalition building across interventions has also been discussed during the 2014 and 2016 Global Vaccine and Immunization Research Forums and the 2016 Geneva Health Forum, as well as in numerous publications including a special issue of Health Affairs in February 2016. The December 2016 expert panel concluded that while progress has been made, additional efforts will be necessary to have a more fully formulated assessment of the FPHV of vaccines included into the evidence-base for the value proposition and analysis of unmet medical need to prioritize vaccine development, vaccine licensure, implementation policies and financing decisions. The desired

A brief history of vaccines: smallpox to the present.

Science.gov (United States)

Hsu, Jennifer L

2013-01-01

Modern vaccine history began in the late 18th century with the discovery of smallpox immunization by Edward Jenner. This pivotal step led to substantial progress in prevention of infectious diseases with inactivated vaccines for multiple infectious diseases, including typhoid, plague and cholera. Each advance produced significant decreases in infection-associated morbidity and mortality, thus shaping our modem cultures. As knowledge of microbiology and immunology grew through the 20th century, techniques were developed for cell culture of viruses. This allowed for rapid advances in prevention of polio, varicella, influenza and others. Finally, recent research has led to development of alternative vaccine strategies through use of vectored antigens, pathogen subunits (purified proteins or polysaccharides) or genetically engineered antigens. As the science of vaccinology continues to rapidly evolve, knowledge of the past creates added emphasis on the importance of developing safe and effective strategies for infectious disease prevention in the 21st century.

Vaccine development: From concept to early clinical testing.

Science.gov (United States)

Cunningham, Anthony L; Garçon, Nathalie; Leo, Oberdan; Friedland, Leonard R; Strugnell, Richard; Laupèze, Béatrice; Doherty, Mark; Stern, Peter

2016-12-20

In the 21st century, an array of microbiological and molecular allow antigens for new vaccines to be specifically identified, designed, produced and delivered with the aim of optimising the induction of a protective immune response against a well-defined immunogen. New knowledge about the functioning of the immune system and host pathogen interactions has stimulated the rational design of vaccines. The design toolbox includes vaccines made from whole pathogens, protein subunits, polysaccharides, pathogen-like particles, use of viral/bacterial vectors, plus adjuvants and conjugation technology to increase and broaden the immune response. Processes such as recombinant DNA technology can simplify the complexity of manufacturing and facilitate consistent production of large quantities of antigen. Any new vaccine development is greatly enhanced by, and requires integration of information concerning: 1. Pathogen life-cycle & epidemiology. Knowledge of pathogen structure, route of entry, interaction with cellular receptors, subsequent replication sites and disease-causing mechanisms are all important to identify antigens suitable for disease prevention. The demographics of infection, specific risk groups and age-specific infection rates determine which population to immunise, and at what age. 2. Immune control & escape. Interactions between the host and pathogen are explored, with determination of the relative importance of antibodies, T-cells of different types and innate immunity, immune escape strategies during infection, and possible immune correlates of protection. This information guides identification and selection of antigen and the specific immune response required for protection. 3. Antigen selection & vaccine formulation. The selected antigen is formulated to remain suitably immunogenic and stable over time, induce an immune response that is likely to be protective, plus be amenable to eventual scale-up to commercial production. 4. Vaccine preclinical

Bacterial superglue enables easy development of efficient virus-like particle based vaccines

DEFF Research Database (Denmark)

Thrane, Susan; Janitzek, Christoph M; Matondo, Sungwa

2016-01-01

BACKGROUND: Virus-like particles (VLPs) represent a significant advance in the development of subunit vaccines, combining high safety and efficacy. Their particulate nature and dense repetitive subunit organization makes them ideal scaffolds for display of vaccine antigens. Traditional approaches...... for VLP-based antigen display require labor-intensive trial-and-error optimization, and often fail to generate dense antigen display. Here we utilize the split-intein (SpyTag/SpyCatcher) conjugation system to generate stable isopeptide bound antigen-VLP complexes by simply mixing of the antigen and VLP......). CONCLUSIONS: The spy-VLP system constitutes a versatile and rapid method to develop highly immunogenic VLP-based vaccines. Our data provide proof-of-concept for the technology's ability to present complex vaccine antigens to the immune system and elicit robust functional antibody responses as well...

Roadmap to developing a recombinant coronavirus S protein receptor-binding domain vaccine for severe acute respiratory syndrome

Science.gov (United States)

Jiang, Shibo; Bottazzi, Maria Elena; Du, Lanying; Lustigman, Sara; Tseng, Chien-Te Kent; Curti, Elena; Jones, Kathryn; Zhan, Bin; Hotez, Peter J

2013-01-01

A subunit vaccine, RBD-S, is under development to prevent severe acute respiratory syndrome (SARS) caused by SARS coronavirus (SARS-CoV), which is classified by the US NIH as a category C pathogen. This vaccine is comprised of a recombinant receptor-binding domain (RBD) of the SARS-CoV spike (S) protein and formulated on alum, together with a synthetic glucopyranosyl lipid A. The vaccine would induce neutralizing antibodies without causing Th2-type immunopathology. Vaccine development is being led by the nonprofit product development partnership; Sabin Vaccine Institute and Texas Children’s Hospital Center for Vaccine Development in collaboration with two academic partners (the New York Blood Center and University of Texas Medical Branch); an industrial partner (Immune Design Corporation); and Walter Reed Army Institute of Research. A roadmap for the product development of the RBD-S SARS vaccine is outlined with a goal to manufacture the vaccine for clinical testing within the next 5 years. PMID:23252385

Active Vaccines for Alzheimer Disease Treatment.

Science.gov (United States)

Sterner, Rosalie M; Takahashi, Paul Y; Yu Ballard, Aimee C

2016-09-01

Vaccination against peptides specific to Alzheimer disease may generate an immune response that could help inhibit disease and symptom progression. PubMed and Scopus were searched for clinical trial articles, review articles, and preclinical studies relevant to the field of active Alzheimer disease vaccines and raw searches yielded articles ranging from 2016 to 1973. ClinicalTrials.gov was searched for active Alzheimer disease vaccine trials. Manual research and cross-referencing from reviews and original articles was performed. First generation Aβ42 phase 2a trial in patients with mild to moderate Alzheimer disease resulted in cases of meningoencephalitis in 6% of patients, so next generation vaccines are working to target more specific epitopes to induce a more controlled immune response. Difficulty in developing these vaccines resides in striking a balance between providing a vaccine that induces enough of an immune response to actually clear protein sustainably but not so much of a response that results in excess immune activation and possibly adverse effects such as meningoencephalitis. Although much work still needs to be done in the field to make this a practical possibility, the enticing allure of being able to treat or even prevent the extraordinarily impactful disease that is Alzheimer disease makes the idea of active vaccination for Alzheimer disease very appealing and something worth striving toward. Copyright © 2016 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.

Reverse Genetics Approaches for the Development of Influenza Vaccines

Science.gov (United States)

Nogales, Aitor; Martínez-Sobrido, Luis

2016-01-01

Influenza viruses cause annual seasonal epidemics and occasional pandemics of human respiratory disease. Influenza virus infections represent a serious public health and economic problem, which are most effectively prevented through vaccination. However, influenza viruses undergo continual antigenic variation, which requires either the annual reformulation of seasonal influenza vaccines or the rapid generation of vaccines against potential pandemic virus strains. The segmented nature of influenza virus allows for the reassortment between two or more viruses within a co-infected cell, and this characteristic has also been harnessed in the laboratory to generate reassortant viruses for their use as either inactivated or live-attenuated influenza vaccines. With the implementation of plasmid-based reverse genetics techniques, it is now possible to engineer recombinant influenza viruses entirely from full-length complementary DNA copies of the viral genome by transfection of susceptible cells. These reverse genetics systems have provided investigators with novel and powerful approaches to answer important questions about the biology of influenza viruses, including the function of viral proteins, their interaction with cellular host factors and the mechanisms of influenza virus transmission and pathogenesis. In addition, reverse genetics techniques have allowed the generation of recombinant influenza viruses, providing a powerful technology to develop both inactivated and live-attenuated influenza vaccines. In this review, we will summarize the current knowledge of state-of-the-art, plasmid-based, influenza reverse genetics approaches and their implementation to provide rapid, convenient, safe and more effective influenza inactivated or live-attenuated vaccines. PMID:28025504

Biologic interactions between HSV-2 and HIV-1 and possible implications for HSV vaccine development.

Science.gov (United States)

Schiffer, Joshua T; Gottlieb, Sami L

2017-09-25

Development of a safe and effective vaccine against herpes simplex virus type 2 (HSV-2) has the potential to limit the global burden of HSV-2 infection and disease, including genital ulcer disease and neonatal herpes, and is a global sexual and reproductive health priority. Another important potential benefit of an HSV-2 vaccine would be to decrease HIV infections, as HSV-2 increases the risk of HIV-1 acquisition several-fold. Acute and chronic HSV-2 infection creates ulcerations and draws dendritic cells and activated CD4+ T cells into genital mucosa. These cells are targets for HIV entry and replication. Prophylactic HSV-2 vaccines (to prevent infection) and therapeutic vaccines (to modify or treat existing infections) are currently under development. By preventing or modifying infection, an effective HSV-2 vaccine could limit HSV-associated genital mucosal inflammation and thus HIV risk. However, a vaccine might have competing effects on HIV risk depending on its mechanism of action and cell populations generated in the genital mucosa. In this article, we review biologic interactions between HSV-2 and HIV-1, consider HSV-2 vaccine development in the context of HIV risk, and discuss implications and research needs for future HSV vaccine development. Copyright © 2017 Elsevier Ltd. All rights reserved.

Phase I trial of RV3-BB rotavirus vaccine: a human neonatal rotavirus vaccine.

Science.gov (United States)

Danchin, M; Kirkwood, C D; Lee, K J; Bishop, R F; Watts, E; Justice, F A; Clifford, V; Cowley, D; Buttery, J P; Bines, J E

2013-05-28

RV3 is a human neonatal rotavirus strain (G3P[6]) that has been associated with asymptomatic neonatal infection and replicates well in the infant gut. RV3-BB rotavirus vaccine has been developed as a rotavirus vaccine candidate for administration at birth. A single-centre, double-blind, randomised placebo-controlled Phase I study evaluated the safety and tolerability of a single oral dose of the second generation RV3-BB rotavirus vaccine (8.3×10(6)FFU/mL) in 20 adults, 20 children and 20 infants (10 vaccine and 10 placebo per age cohort). Vaccine take was defined as seroconversion (a 3-fold increase in serum anti-rotavirus IgA or serum neutralising antibody (SNA) from baseline at day 28 post-dose) or evidence of RV3-BB viral replication in the faeces by RT-PCR analysis 3-6 days post-vaccination. RV3-BB presence was confirmed by sequence analysis. The RV3-BB vaccine was well tolerated in all participants, with no pattern of adverse events shown to be associated with the study vaccine. In the infant cohort, vaccine take was demonstrated in 8/9 infants following a single dose of vaccine compared with 2/7 placebo recipients. In the infant vaccine group, 5/9 infants exhibited either IgA or SNA seroconversion and 7/9 infants had evidence of RV3-BB replication on days 3-6, compared with 2/7 infants who seroconverted and 0/10 infants with evidence of replication in the placebo group. Two infants in the placebo group had serological evidence of a rotavirus infection within the 28-day study period: one demonstrated an IgA and the other an SNA response, with wild-type virus replication detected in another infant. A single dose of RV3-BB rotavirus vaccine was well tolerated in adults, children and infants. Most infants (8/9) who received RV3-BB demonstrated vaccine take following a single dose. These data support progression of RV3-BB to Phase II immunogenicity and efficacy trials. Copyright © 2013 Elsevier Ltd. All rights reserved.

Clinical development of a novel inactivated poliomyelitis vaccine based on attenuated Sabin poliovirus strains.

Science.gov (United States)

Verdijk, Pauline; Rots, Nynke Y; Bakker, Wilfried A M

2011-05-01

Following achievement of polio eradication, the routine use of all live-attenuated oral poliovirus vaccines should be discontinued. However, the costs per vaccine dose for the alternative inactivated poliovirus vaccine (IPV) are significantly higher and the current production capacity is not sufficient for worldwide distribution of the vaccine. In order to achieve cost-prize reduction and improve affordability, IPV production processes and dose-sparing strategies should be developed to facilitate local manufacture at a relatively lower cost. The use of attenuated Sabin instead of wild-type polio strains will provide additional safety during vaccine production and permits production in low-cost settings. Sabin-IPV is under development by several manufacturers. This article gives an overview of results from clinical trials with Sabin-IPV and discusses the requirements and challenges in the clinical development of this novel IPV.

Development of an Integrated Immunology and Vaccines Pharmacy Elective

Directory of Open Access Journals (Sweden)

Stephanie F James

2017-07-01

Full Text Available Objective: To describe an elective course on immunology and vaccines for pharmacy students that extends beyond basic immunization training. Design: A three credit-hour Immunology and Vaccines elective was developed and taught by an immunologist, policy research expert, and pharmacist. The learning objectives of the course included: understanding how the immune system works with vaccines to provide protection against infectious diseases, the history and policies involved in immunization practice, and how to counsel the vaccine hesitant individual. Classes were conducted using a variety of formats; group projects, lectures, films, literature reviews and guest speakers. An end-of-course evaluation was used to gauge student opinion on course value. Students were evaluated by four exams and a final group presentation. Conclusion: Students indicated that this course was valuable to their future pharmacy careers and provided insight into why people choose not to vaccinate and how they could use the course insight to properly educate such individuals. Conflict of Interest We declare no conflicts of interest or financial interests that the authors or members of their immediate families have in any product or service discussed in the manuscript, including grants (pending or received, employment, gifts, stock holdings or options, honoraria, consultancies, expert testimony, patents and royalties   Type: Note

The Capricious Nature of Bacterial Pathogens: Phasevarions and Vaccine Development

Directory of Open Access Journals (Sweden)

Aimee Tan

2016-12-01

Full Text Available Infectious diseases are a leading cause of morbidity and mortality worldwide, and vaccines are one of the most successful and cost-effective tools for disease prevention. One of the key considerations for rational vaccine development is the selection of appropriate antigens. Antigens must induce a protective immune response, and this response should be directed to stably expressed antigens so the target microbe can always be recognized by the immune system. Antigens with variable expression, due to environmental signals or phase variation (i.e., high frequency, random switching of expression, are not ideal vaccine candidates because variable expression could lead to immune evasion. Phase variation is often mediated by the presence of highly mutagenic simple tandem DNA repeats, and genes containing such sequences can be easily identified, and their use discounted as vaccine antigens reconsidered. Recent research has identified phase variably expressed DNA methyltransferases that act as global epigenetic regulators. These phase variable regulons, known as phasevarions, are associated with altered virulence phenotypes and/or expression of vaccine candidates. As such, genes encoding candidate vaccine antigens that have no obvious mechanism of phase variation may be subject to indirect, epigenetic control as part of a phasevarion. Bioinformatic and experimental studies are required to elucidate the distribution and mechanism of action of these DNA methyltransferases, and most importantly, whether they mediate epigenetic regulation of potential and current vaccine candidates. This process is essential to define the stably expressed antigen target profile of bacterial pathogens and thereby facilitate efficient, rational selection of vaccine antigens.

Ebola virus: immune mechanisms of protection and vaccine development.

Science.gov (United States)

Nyamathi, Adeline M; Fahey, John L; Sands, Heather; Casillas, Adrian M

2003-04-01

Vaccination is one of our most powerful antiviral strategies. Despite the emergence of deadly viruses such as Ebola virus, vaccination efforts have focused mainly on childhood communicable diseases. Although Ebola virus was once believed to be limited to isolated outbreaks in distant lands, forces of globalization potentiate outbreaks anywhere in the world through incidental transmission. Moreover, since this virus has already been transformed into weapon-grade material, the potential exists for it to be used as a biological weapon with catastrophic consequences for any population vulnerable to attack. Ebola hemorrhagic fever (EHF) is a syndrome that can rapidly lead to death within days of symptom onset. The disease directly affects the immune system and vascular bed, with correspondingly high mortality rates. Patients with severe disease produce dangerously high levels of inflammatory cytokines, which destroy normal tissue and microcirculation, leading to profound capillary leakage, renal failure, and disseminated intravascular coagulation. Vaccine development has been fraught with obstacles, primarily of a biosafety nature. Case reports of acutely ill patients with EHF showing improvement with the transfusion of convalescent plasma are at odds with animal studies demonstrating further viral replication with the same treatment. Using mRNA extracted from bone marrow of Ebola survivors, human monoclonal antibodies against Ebola virus surface protein have been experimentally produced and now raise the hope for the development of a safe vaccine.

APPROACHING THE TARGET: THE PATH TOWARDS AN EFFECTIVE MALARIA VACCINE

Directory of Open Access Journals (Sweden)

Alberto L. García-Basteiro

2012-01-01

Full Text Available Eliciting an effective malaria vaccine has been the goal of the scientific community for many years. A malaria vaccine, added to existing tools and strategies, would further prevent and decrease the unacceptable malaria morbidity and mortality burden. Great progress has been made over the last decade, with some vaccine candidates in the clinical phases of development. The RTS,S malaria vaccine candidate, based on a recombinant P. falciparum protein, is the most advanced of such candidates, currently undergoing a large phase III trial. RTS,S has consistently shown an efficacy of around 50% against the first clinical episode of malaria, with protection in some cases extending up to 4 years of duration. Thus, it is hoped that this candidate vaccine will eventually become the first licensed malaria vaccine. This first vaccine against a human parasite is a groundbreaking achievement, but improved malaria vaccines conferring higher protection will be needed if the aspiration of malaria eradication is to be achieved

Prospects and perspectives for development of a vaccine against herpes simplex virus infections.

Science.gov (United States)

McAllister, Shane C; Schleiss, Mark R

2014-11-01

Herpes simplex viruses 1 and 2 are human pathogens that lead to significant morbidity and mortality in certain clinical settings. The development of effective antiviral medications, however, has had little discernible impact on the epidemiology of these pathogens, largely because the majority of infections are clinically silent. Decades of work have gone into various candidate HSV vaccines, but to date none has demonstrated sufficient efficacy to warrant licensure. This review examines developments in HSV immunology and vaccine development published since 2010, and assesses the prospects for improved immunization strategies that may result in an effective, licensed vaccine in the near future.

Progress toward a universal H5N1 vaccine: a recombinant modified vaccinia virus Ankara-expressing trivalent hemagglutinin vaccine.

Directory of Open Access Journals (Sweden)

Mookkan Prabakaran

Full Text Available The rapid evolution of new sublineages of H5N1 influenza poses the greatest challenge in control of H5N1 infection by currently existing vaccines. To overcome this, an MVAtor vector expressing three H5HA antigens A/Vietnam/1203/04, A/Indonesia/669/06 and A/Anhui/01/05 (MVAtor-tri-HA vector was developed to elicit broad cross-protection against diverse clades by covering amino acid variations in the major neutralizing epitopes of HA among H5N1 subtypes.BALB/c mice and guinea pigs were immunized i.m. with 8×107 TCID50/animal of MVAtor-tri-HA vector. The immunogenicity and cross-protective immunity of the MVAtor-tri-HA vector was evaluated against diverse clades of H5N1 strains.The results showed that mice immunized with MVAtor-tri-HA vector induced robust cross-neutralizing immunity to diverse H5N1 clades. In addition, the MVAtor-tri-HA vector completely protected against 10 MLD50 of a divergent clade of H5N1 infection (clade 7. Importantly, the serological surveillance of post-vaccinated guinea pig sera demonstrated that MVAtor-tri-HA vector was able to elicit strong cross-clade neutralizing immunity against twenty different H5N1 strains from six clades that emerged between 1997 and 2012.The present findings revealed that incorporation of carefully selected HA genes from divergent H5N1 strains within a single vector could be an effective approach in developing a vaccine with broad coverage to prevent infection during a pandemic situation.

Recent updates and perspectives on approaches for the development of vaccines against visceral leishmaniasis

Directory of Open Access Journals (Sweden)

Mariana Costa Duarte

Full Text Available Abstract: Visceral leishmaniasis (VL is one of the most important tropical diseases worldwide. Although chemotherapy has been widely used to treat this disease, problems related to the development of parasite resistance and side effects associated with the compounds used have been noted. Hence, alternative approaches for VL control are desirable. Some methods, such as vector control and culling of infected dogs, are insufficiently effective, with the latter not ethically recommended. The development of vaccines to prevent VL is a feasible and desirable measure for disease control; for example, some vaccines designed to protect dogs against VL have recently been brought to market. These vaccines are based on the combination of parasite fractions or recombinant proteins with adjuvants that are able to induce cellular immune responses; however, their partial efficacy and the absence of a vaccine to protect against human leishmaniasis underline the need for characterization of new vaccine candidates. This review presents recent advances in control measures for VL based on vaccine development, describing extensively studied antigens, as well as new antigenic proteins recently identified using immuno-proteomic techniques.

Business models and opportunities for cancer vaccine developers.

Science.gov (United States)

Kudrin, Alex

2012-10-01

Despite of growing oncology pipeline, cancer vaccines contribute only to a minor share of total oncology-attributed revenues. This is mainly because of a limited number of approved products and limited sales from products approved under compassionate or via early access entry in smaller and less developed markets. However revenue contribution from these products is extremely limited and it remains to be established whether developers are breaking even or achieving profitability with existing sales. Cancer vaccine field is well recognized for high development costs and risks, low historical rates of investment return and high probability of failures arising in ventures, partnerships and alliances. The cost of reimbursement for new oncology agents is not universally acceptable to payers limiting the potential for a global expansion, market access and reducing probability of commercial success. In addition, the innovation in cancer immunotherapy is currently focused in small and mid-size biotech companies and academic institutions struggling for investment. Existing R&D innovation models are deemed unsustainable in current "value-for-money" oriented healthcare environment. New business models should be much more open to collaborative, networked and federated styles, which could help to outreach global, markets and increase cost-efficiencies across an entire value chain. Lessons learned from some developing countries and especially from South Korea illustrate that further growth of cancer vaccine industry will depends not only on new business models but also will heavily rely on regional support and initiatives from different bodies, such as governments, payers and regulatory bodies.

Neonatal tetanus elimination in Pakistan: progress and challenges.

Science.gov (United States)

Lambo, Jonathan A; Nagulesapillai, Tharsiya

2012-12-01

Pakistan is one of the 34 countries that have not achieved the neonatal tetanus (NT) global elimination target set by the World Health Organization (WHO). NT, caused by Clostridium tetani, is a highly fatal infection of the neonatal period. It is one of the most underreported diseases and remains a major but preventable cause of neonatal and infant mortality in many developing countries. In 1989, the World Health Assembly called for the elimination of NT by 1995, and since then considerable progress has been made using the following strategies: clean delivery practices, routine tetanus toxoid (TT) immunization of pregnant women, and immunization of all women of childbearing age with three doses of TT vaccine in high-risk areas during supplementary immunization campaigns. This review presents the activities, progress, and challenges in achieving NT elimination in Pakistan. A review of the literature found TT vaccination coverage in Pakistan ranged from 60% to 74% over the last decade. Low vaccination coverage, the main driver for NT in Pakistan, is due to many factors, including demand failure for TT vaccine resulting from inadequate knowledge of TT vaccine among reproductive age females and inadequate information about the benefits of TT provided by health care workers and the media. Other factors linked to low vaccination coverage include residing in rural areas, lack of formal education, poor knowledge about place and time to get vaccinated, and lack of awareness about the importance of vaccination. A disparity exists in TT vaccination coverage and antenatal care between urban and rural areas due to access and utilization of health care services. NT reporting is incomplete, as cases from the private sector and rural areas are underreported. To successfully eliminate NT, women of reproductive age must be made aware of the benefits of TT vaccine, not only to themselves, but also to their families. Effective communication strategies for TT vaccine delivery and

Pre-clinical and clinical development of the first placental malaria vaccine

DEFF Research Database (Denmark)

Pehrson, Caroline; Salanti, Ali; Theander, Thor G

2017-01-01

the condition.  Areas covered: Pub Med was searched using the broad terms 'malaria parasite placenta' to identify studies of interactions between parasite and host, 'prevention of placental malaria' to identify current strategies to prevent placental malaria, and 'placental malaria vaccine' to identify pre-clinical...... vaccine development. However, all papers from these searches were not systematically included.  Expert commentary: The first phase I clinical trials of vaccines are well underway. Trials testing efficacy are more complicated to carry out as only women that are exposed to parasites during pregnancy...

Polymeric micro/nanoparticles: Particle design and potential vaccine delivery applications.

Science.gov (United States)

Yue, Hua; Ma, Guanghui

2015-11-04

Particle based adjuvant showed promising signs on delivering antigen to immune cells and acting as stimulators to elicit preventive or therapeutic response. Nevertheless, the wide size distribution of available polymeric particles has so far obscured the immunostimulative effects of particle adjuvant, and compromised the progress in pharmacological researches. To conquer this hurdle, our research group has carried out a series of researches regarding the particulate vaccine, by taking advantage of the successful fabrication of polymeric particles with uniform size. In this review, we highlight the insight and practical progress focused on the effects of physiochemical property (e.g. particle size, charge, hydrophobicity, surface chemical group, and particle shape) and antigen loading mode on the resultant biological/immunological outcome. The underlying mechanisms of how the particles-based vaccine functioned in the immune system are also discussed. Based on the knowledge, particles with high antigen payload and optimized attributes could be designed for expected adjuvant purpose, leading to the development of high efficient vaccine candidates. Copyright © 2015 Elsevier Ltd. All rights reserved.

History of vaccination.

Science.gov (United States)

Plotkin, Stanley

2014-08-26

Vaccines have a history that started late in the 18th century. From the late 19th century, vaccines could be developed in the laboratory. However, in the 20th century, it became possible to develop vaccines based on immunologic markers. In the 21st century, molecular biology permits vaccine development that was not possible before.

History of vaccination

OpenAIRE

Plotkin, Stanley

2014-01-01

Vaccines have a history that started late in the 18th century. From the late 19th century, vaccines could be developed in the laboratory. However, in the 20th century, it became possible to develop vaccines based on immunologic markers. In the 21st century, molecular biology permits vaccine development that was not possible before.

Adjuvants are key factors for the development of future vaccines: Lessons from the Finlay Adjuvant platform

Directory of Open Access Journals (Sweden)

Oliver ePérez

2013-12-01

Full Text Available The development of effective vaccines against neglected diseases, especially those associated with poverty and social deprivation, is urgently needed. Modern vaccine technologies and a better understanding of the immune response have provided scientists with the tools for rational and safer design of subunit vaccines. Often, however, subunit vaccines do not elicit strong immune responses, highlighting the need to incorporate better adjuvants; this step therefore becomes a key factor for vaccine development. In this review we outline some key features of modern vaccinology that are linked with the development of better adjuvants. In line with the increased desire to obtain novel adjuvants for future vaccines, the Finlay Adjuvant Platform offers a novel approach for the development of new and effective adjuvants. The Finlay Adjuvants (AFs, AFPL (proteoliposome and AFCo (cochleate, were initially designed for parenteral and mucosal applications, and constitute potent adjuvants for the induction of Th1 responses against several antigens. This review summarizes the status of the Finlay technology in producing promising adjuvants for unsolved-vaccine diseases including mucosal approaches and therapeutic vaccines. Ideas related to adjuvant classification, adjuvant selection, and their possible influence on innate recognition via multiple toll-like receptors are also discussed.

Ebola Virus Vaccines – reality or fiction?

Science.gov (United States)

Mire, Chad E.; Geisbert, Thomas W.; Feldmann, Heinz

2016-01-01

For 40 years ebolaviruses have been responsible for sporadic outbreaks of severe and often fatal hemorrhagic fever in humans and nonhuman primates. In December 2013 an unprecedented Zaire ebolavirus epidemic began in West Africa. Although “patient zero” has finally been reached after 2 years, the virus is again causing disease in the region. Currently there are no licensed vaccines or therapeutic countermeasures against ebolaviruses; however, the epidemic in West Africa has focused attention on the potential vaccine platforms developed over the past 15 years. There has been remarkable progress using a variety of platforms including DNA, subunit, and several viral vector approaches, replicating and non-replicating, which have shown varying degrees of protective efficacy in the “gold-standard” nonhuman primate models for Ebolavirus infections. A number of these vaccine platforms have moved into clinical trials over the past year with the hope of finding an efficacious vaccine to prevent future outbreaks/epidemics of Ebola hemorrhagic fever on the scale of the West African epidemic. PMID:27078187

Vaccines today, vaccines tomorrow: a perspective

OpenAIRE

Loucq, Christian

2013-01-01

Vaccines are considered as one of the major contributions of the 20th century and one of the most cost effective public health interventions. The International Vaccine Institute has as a mission to discover, develop and deliver new and improved vaccines against infectious diseases that affects developing nations. If Louis Pasteur is known across the globe, vaccinologists like Maurice Hilleman, Jonas Salk and Charles M?rieux are known among experts only despite their contribution to global hea...

Rotavirus epidemiology and vaccine demand: considering Bangladesh chapter through the book of global disease burden.

Science.gov (United States)

Mahmud-Al-Rafat, Abdullah; Muktadir, Abdul; Muktadir, Hasneen; Karim, Mahbubul; Maheshwari, Arpan; Ahasan, Mohammad Mainul

2018-02-01

Rotavirus is the major cause of gastroenteritis in children throughout the world. Every year, a large number of children aged rotavirus-related diarrhoeal diseases. Though these infections are vaccine-preventable, the vast majority of children in low-income countries suffer from the infection. The situation leads to severe economic loss and constitutes a major public health problem. We searched electronic databases including PubMed and Google scholar using the following words: "features of rotavirus," "epidemiology of rotavirus," "rotavirus serotypes," "rotavirus in Bangladesh," "disease burden of rotavirus," "rotavirus vaccine," "low efficacy of rotavirus vaccine," "inactivated rotavirus vaccine". Publications until July 2017 have been considered for this work. Currently, two live attenuated vaccines are available throughout the world. Many countries have included rotavirus vaccines in national immunization program to reduce the disease burden. However, due to low efficacy of the available vaccines, satisfactory outcome has not yet been achieved in developing countries such as Bangladesh. Poor economic, public health, treatment, and sanitation status of the low-income countries necessitate the need for the most effective rotavirus vaccines. Therefore, the present scenario demands the development of a highly effective rotavirus vaccine. In this regard, inactivated rotavirus vaccine concept holds much promise for reducing the current disease burden. Recent advancements in developing an inactivated rotavirus vaccine indicate a significant progress towards disease prophylaxis and control.

Development of vaccines against Plasmodium falciparum malaria: taking lessons from naturally acquired protective immunity

DEFF Research Database (Denmark)

Hviid, Lars

2007-01-01

The acquisition of substantial anti-malarial protection in people naturally exposed to P. falciparum is often cited as evidence that malaria vaccines can be developed, but is rarely used to guide the development. We are pursuing the development of vaccines based on antigens and immune responses...

Development of a novel oral vaccine against Mycobacterium avium paratuberculosis and Johne disease

Science.gov (United States)

Johnston, C; Coffey, A; Sleator, RD

2010-01-01

Mycobacterium avium subsp. paratuberculosis (MAP) is the etiological agent of Johne disease, a granulomatous enteritis of cattle and other domesticated and wild ruminant species. Johne disease is prevalent worldwide and has a significant impact on the global agricultural economy. Current vaccines against Johne are insufficient in stemming its spread, and associated side-effects prevent their widespread use in control programs. Effective and safe vaccine strategies are needed. The main purpose of this paper is to propose and evaluate the development of a novel oral subunit-vaccine using a patho-biotechnological approach. This novel strategy, which harnesses patho-genetic elements from the intracellular pathogen Listeria monocytogenes, may provide a realistic route towards developing an effective next generation subunit vaccine against Johne disease and paratuberculosis. PMID:21326921

A real options approach to biotechnology investment policy-the case of developing a Campylobacter vaccine to poultry.

Science.gov (United States)

Lund, Mogens; Jensen, Jørgen Dejgård

2016-06-01

The aim of the article is to identify and analyse public-private incentives for the development and marketing of new animal vaccines within a real options methodological framework, and to investigate how real options methodology can be utilized to support economic incentives for vaccine development in a cost-effective way. The development of a vaccine against Campylobacter jejuni in poultry is applied as a case study. Employing the real options methodology, the net present value of the vaccine R&D project becomes larger than a purely probabilistic expected present value throughout the different stages of the project - and the net present value becomes larger, when more types of real options are taken into consideration. The insight from the real options analysis reveals opportunities for new policies to promote the development of animal vaccines. One such approach might be to develop schemes combining stage-by-stage optimized subsidies in the individual development stages, with proper account taken of investors'/developers' economic incentives to proceed, sell or cancel the project in the respective stages. Another way of using the real options approach to support the development of desirable animal vaccines could be to issue put options for the vaccine candidate, enabling vaccine developers to hedge against the economic risk from market volatility. Copyright © 2016 Elsevier B.V. All rights reserved.

Recent advances in canine leptospirosis: focus on vaccine development

Directory of Open Access Journals (Sweden)

Klaasen HLBM

2015-06-01

Full Text Available Henricus LBM (Eric Klaasen,1 Ben Adler2 1Global Companion Animals Research and Development, Merck Sharp and Dohme Animal Health, Boxmeer, the Netherlands; 2Department of Microbiology, Monash University, Clayton, VIC, Australia Abstract: Leptospirosis is a global infection of humans and animals caused by pathogenic Leptospira spp. Leptospirosis is a major zoonosis, with infection acquired from wild and domestic animals. It is also a significant cause of morbidity, mortality, and economic loss in production and companion animals. Leptospirosis in dogs is prevalent worldwide and as well as a cause of canine disease, it presents a zoonotic risk to human contacts. Canine leptospirosis does not differ greatly from the syndromes seen in other animal species, with hepatic, renal, and pulmonary involvement being the main manifestations. While the pathogenesis of disease is well documented at the whole animal level, the cellular and molecular basis remains obscure. Killed, whole-cell bacterin vaccines are licensed worldwide and have not changed greatly over the past several decades. Vaccine-induced immunity is restricted to serologically related serovars and is generally short-lived, necessitating annual revaccination. The appearance of new serovars as causes of canine leptospirosis requires constant epidemiological surveillance and tailoring of vaccines to cover emerging serovars. At the present time, there is no realistic prospect of alternative, non-bacterin vaccines in the foreseeable future. Keywords: canine leptospirosis, vaccines, diagnosis, epidemiology, pathogenesis

Development and initial feedback about a human papillomavirus (HPV) vaccine comic book for adolescents.

Science.gov (United States)

Katz, Mira L; Oldach, Benjamin R; Goodwin, Jennifer; Reiter, Paul L; Ruffin, Mack T; Paskett, Electra D

2014-06-01

Human papillomavirus (HPV) vaccination rates do not meet the Healthy People 2020 objective of 80% coverage among adolescent females. We describe the development and initial feedback about an HPV vaccine comic book for young adolescents. The comic book is one component of a multilevel intervention to improve HPV vaccination rates among adolescents. Parents suggested and provided input into the development of a HPV vaccine comic book. Following the development of the comic book, we conducted a pilot study to obtain initial feedback about the comic book among parents (n = 20) and their adolescents ages 9 to 14 (n = 17) recruited from a community-based organization. Parents completed a pre-post test including items addressing HPV knowledge, HPV vaccine attitudes, and about the content of the comic book. Adolescents completed a brief interview after reading the comic book. After reading the comic book, HPV knowledge improved (2.7 to 4.6 correct answers on a 0-5 scale; p book's content was acceptable and adolescents liked the story, found it easy to read, and thought the comic book was a good way to learn about being healthy. Parents provided valuable information in the development of a theoretically-based comic book and the comic book appears to be an acceptable format for providing HPV vaccine information to adolescents. Future research will include the comic book in an intervention study to improve HPV vaccination rates.

Progression of pancreatic adenocarcinoma is significantly impeded with a combination of vaccine and COX-2 inhibition.

Science.gov (United States)

Mukherjee, Pinku; Basu, Gargi D; Tinder, Teresa L; Subramani, Durai B; Bradley, Judy M; Arefayene, Million; Skaar, Todd; De Petris, Giovanni

2009-01-01

With a 5-year survival rate of <5%, pancreatic cancer is one of the most rapidly fatal malignancies. Current protocols for the treatment of pancreas cancer are not as effective as we desire. In this study, we show that a novel Mucin-1 (MUC1)-based vaccine in combination with a cyclooxygenase-2 inhibitor (celecoxib), and low-dose chemotherapy (gemcitabine) was effective in preventing the progression of preneoplastic intraepithelial lesions to invasive pancreatic ductal adenocarcinomas. The study was conducted in an appropriate triple transgenic model of spontaneous pancreatic cancer induced by the KRAS(G12D) mutation and that expresses human MUC1 as a self molecule. The combination treatment elicited robust antitumor cellular and humoral immune responses and was associated with increased apoptosis in the tumor. The mechanism for the increased immune response was attributed to the down-regulation of circulating prostaglandin E(2) and indoleamine 2, 3,-dioxygenase enzymatic activity, as well as decreased levels of T regulatory and myeloid suppressor cells within the tumor microenvironment. The preclinical data provide the rationale to design clinical trials with a combination of MUC1-based vaccine, celecoxib, and gemcitabine for the treatment of pancreatic cancer.

[Ten years of human papillomavirus vaccination. From dermatology to oncology via infectology].

Science.gov (United States)

Moraga-Llop, Fernando A

2018-05-01

Human papillomavirus (HPV) was first identified in dermatology, and it was subsequently demonstrated that is was required for the development of uterine cervical cancer and other tumours, after a persistent infection by any of its oncogenic genotypes. Ten years ago, the most common infections and cancers associated with HPV could be prevented by immunisation with 2vaccines, one bivalent, and another tetravalent, and having just marketed a nonavalent one. During the period 2007-2008, the HPV vaccine was included in the Autonomous Communities vaccination calendar, and it is the second vaccine, after that of Hepatitis B, that prevents cancer. In these 10 years that these vaccines have been available the knowledge has progressed and there have been significant advances in vaccination strategies, as well as in the indications and recommendations. These include, lowering the age in the vaccination schedule, prescribing of 2doses at 9 years and at 13-14 years, systematic vaccination of the male in some countries, immunisation of the woman after adolescence, implementation of vaccination programmes in developed countries, prevention of other cancers, recommendations for vaccinations for populations at high risk of HPV infection, scientific evidence on the impact and effectiveness of vaccination, and confirmation of the safety of these vaccines, with more than 270 million doses administered, as has already been observed in clinical trials. The role of health professionals is essential to achieve and maintain high vaccine coverage. Copyright © 2017 Asociación Española de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

GeVaDSs – decision support system for novel Genetic Vaccine development process

Directory of Open Access Journals (Sweden)

Blazewicz Jacek

2012-05-01

Full Text Available Abstract Background The lack of a uniform way for qualitative and quantitative evaluation of vaccine candidates under development led us to set up a standardized scheme for vaccine efficacy and safety evaluation. We developed and implemented molecular and immunology methods, and designed support tools for immunization data storage and analyses. Such collection can create a unique opportunity for immunologists to analyse data delivered from their laboratories. Results We designed and implemented GeVaDSs (Genetic Vaccine Decision Support system an interactive system for efficient storage, integration, retrieval and representation of data. Moreover, GeVaDSs allows for relevant association and interpretation of data, and thus for knowledge-based generation of testable hypotheses of vaccine responses. Conclusions GeVaDSs has been tested by several laboratories in Europe, and proved its usefulness in vaccine analysis. Case study of its application is presented in the additional files. The system is available at: http://gevads.cs.put.poznan.pl/preview/(login: viewer, password: password.

Deinococcus Mn2+-peptide complex: A novel approach to alphavirus vaccine development.

Science.gov (United States)

Gayen, Manoshi; Gupta, Paridhi; Morazzani, Elaine M; Gaidamakova, Elena K; Knollmann-Ritschel, Barbara; Daly, Michael J; Glass, Pamela J; Maheshwari, Radha K

2017-06-22

Over the last ten years, Chikungunya virus (CHIKV), an Old World alphavirus has caused numerous outbreaks in Asian and European countries and the Americas, making it an emerging pathogen of great global health importance. Venezuelan equine encephalitis virus (VEEV), a New World alphavirus, on the other hand, has been developed as a bioweapon in the past due to its ease of preparation, aerosol dispersion and high lethality in aerosolized form. Currently, there are no FDA approved vaccines against these viruses. In this study, we used a novel approach to develop inactivated vaccines for VEEV and CHIKV by applying gamma-radiation together with a synthetic Mn-decapeptide-phosphate complex (MnDpPi), based on manganous-peptide-orthophosphate antioxidants accumulated in the extremely radiation-resistant bacterium Deinococcus radiodurans. Classical gamma-irradiated vaccine development approaches are limited by immunogenicity-loss due to oxidative damage to the surface proteins at the high doses of radiation required for complete virus-inactivation. However, addition of MnDpPi during irradiation process selectively protects proteins, but not the nucleic acids, from the radiation-induced oxidative damage, as required for safe and efficacious vaccine development. Previously, this approach was used to develop a bacterial vaccine. In the present study, we show that this approach can successfully be applied to protecting mice against viral infections. Irradiation of VEEV and CHIKV in the presence of MnDpPi resulted in substantial epitope preservation even at supra-lethal doses of gamma-rays (50,000Gy). Irradiated viruses were found to be completely inactivated and safe in vivo (neonatal mice). Upon immunization, VEEV inactivated in the presence of MnDpPi resulted in drastically improved protective efficacy. Thus, the MnDpPi-based gamma-inactivation approach described here can readily be applied to developing vaccines against any pathogen of interest in a fast and cost

The US Military Commitment to Vaccine Development: A Century of Successes and Challenges

Directory of Open Access Journals (Sweden)

Silvia Ratto-Kim

2018-06-01

Full Text Available The US military has been a leading proponent of vaccine development since its founding. General George Washington ordered the entire American army to be variolated against smallpox after recognizing the serious threat that it posed to military operations. He did this on the recommendation from Dr. John Morgan, the physician-in-chief of the American army, who wrote a treatise on variolation in 1776. Although cases of smallpox still occurred, they were far fewer than expected, and it is believed that the vaccination program contributed to victory in the War of Independence. Effective military force requires personnel who are healthy and combat ready for worldwide deployment. Given the geography of US military operations, military personnel should also be protected against diseases that are endemic in potential areas of conflict. For this reason, and unknown to many, the US military has strongly supported vaccine research and development. Four categories of communicable infectious diseases threaten military personnel: (1 diseases that spread easily in densely populated areas (respiratory and dysenteric diseases; (2 vector-borne diseases (disease carried by mosquitoes and other insects; (3 sexually transmitted diseases (hepatitis, HIV, and gonorrhea; and (4 diseases associated with biological warfare. For each category, the US military has supported research that has provided the basis for many of the vaccines available today. Although preventive measures and the development of drugs have provided some relief from the burden of malaria, dengue, and HIV, the US military continues to fund research and development of prophylactic vaccines that will contribute to force health protection and global health. In the past few years, newly recognized infections with Zika, severe acute respiratory syndrome, Middle East respiratory syndrome viruses have pushed the US military to fund research and fast track clinical trials to quickly and effectively develop

Individual moral development and moral progress

OpenAIRE

Schinkel, Anders; de Ruyter, Doret J.

2017-01-01

At first glance, one of the most obvious places to look for moral progress is in individuals, in particular in moral development from childhood to adulthood. In fact, that moral progress is possible is a foundational assumption of moral education. Beyond the general agreement that moral progress is not only possible but even a common feature of human development things become blurry, however. For what do we mean by ‘progress’? And what constitutes moral progress? Does the idea of individual m...

An updated methodology to review developing-country vaccine manufacturer viability.

Science.gov (United States)

Luter, Nicholas; Kumar, Ritu; Hozumi, Dai; Lorenson, Tina; Larsen, Shannon; Gowda, Bhavya; Batson, Amie

2017-07-05

In 1997, Milstien, Batson, and Meaney published "A Systematic Method for Evaluating the Potential Viability of Local Vaccine Producers." The paper identified characteristics of successful vaccine manufacturers and developed a viability framework to evaluate their performance. This paper revisits the original study after two decades to determine the ability of the framework to predict manufacturer success. By reconstructing much of the original dataset and conducting in-depth interviews, the authors developed informed views on the continued viability of manufacturers in low- and middle-income country markets. Considering the marked changes in the market and technology landscape since 1997, the authors find the viability framework to be predictive and a useful lens through which to evaluate manufacturer success or failure. Of particular interest is how incumbent and potentially new developing-country vaccine manufacturers enter and sustain production in competitive international markets and how they integrate (or fail to integrate) new technology into the production process. Ultimately, most manufacturers will need to meet global quality standards to be viable. As governments and donors consider investments in vaccine producers, the updated viability factors will be a useful tool in evaluating the prospects of manufacturers over the mid to long term. The paper emphasizes that while up-front investments are important, other critical factors-including investments in a national regulatory authority, manufacturer independence, and ability to adapt and adopt new technology-are necessary to ensure viability. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Aspergillus vaccines: Hardly worth studying or worthy of hard study?

Science.gov (United States)

Levitz, Stuart M

2017-01-01

Vaccines rank among the greatest advances in the history of public health. Yet, despite the need, there are no licensed vaccines to protect humans against fungal diseases, including aspergillosis. In this focused review, some of the major scientific and logistical challenges to developing vaccines to protect at-risk individuals against aspergillosis are discussed. Approaches that have shown promise in animal models include vaccines that protect against multiple fungal genera and those that are specifically directed to Aspergillus Advances in proteomics and glycomics have facilitated identification of candidate antigens for use in subunit vaccines. Novel adjuvants and delivery systems are becoming available that can skew vaccine responses toward those associated with protection. Immunotherapy consisting of adoptive transfer of Aspergillus-specific T cells to allogeneic hematopoietic transplant recipients has advanced to human testing but is technically difficult and of unproven benefit. While progress has been impressive, much work still needs to be done if vaccines against aspergillosis are to become a reality. © The Author 2016. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Comparison of the nucleotide sequence of wild-type hepatitis - A virus and its attenuated candidate vaccine derivative

International Nuclear Information System (INIS)

Cohen, J.I.; Rosenblum, B.; Ticehurst, J.R.; Daemer, R.; Feinstone, S.; Purcell, R.H.

1987-01-01

Development of attenuated mutants for use as vaccines is in progress for other viruses, including influenza, rotavirus, varicella-zoster, cytomegalovirus, and hepatitis-A virus (HAV). Attenuated viruses may be derived from naturally occurring mutants that infect human or nonhuman hosts. Alternatively, attenuated mutants may be generated by passage of wild-type virus in cell culture. Production of attenuated viruses in cell culture is a laborious and empiric process. Despite previous empiric successes, understanding the molecular basis for attenuation of vaccine viruses could facilitate future development and use of live-virus vaccines. Comparison of the complete nucleotide sequences of wild-type (virulent) and vaccine (attenuated) viruses has been reported for polioviruses and yellow fever virus. Here, the authors compare the nucleotide sequence of wild-type HAV HM-175 with that of a candidate vaccine derivative

A fuzzy MICMAC analysis for improving supply chain performance of basic vaccines in developing countries.

Science.gov (United States)

Chandra, Dheeraj; Kumar, Dinesh

2018-03-01

In recent years, demand to improve child immunization coverage globally, and the development of the latest vaccines and technology has made the vaccine market very complex. The rise in such complexities often gives birth to numerous issues in the vaccine supply chain, which are the primary cause of its poor performance. Figuring out the cause of the performance problem can help you decide how to address it. The goal of the present study is to identify and analyze important issues in the supply chain of basic vaccines required for child immunization in the developing countries. Twenty-five key issues as various factors of the vaccine supply chain have been presented in this paper. Fuzzy MICMAC analysis has been carried out to classify the factors based on their driving and dependence power and to develop a hierarchy based model. Further, the findings have been discussed with the field experts to identify the critical factors. Three factors: better demand forecast, communication between the supply chain members, and proper planning and scheduling have been identified as the critical factors of vaccine supply chain. These factors should be given special care to improve vaccine supply chain performance.

Modelling efforts needed to advance herpes simplex virus (HSV) vaccine development: Key findings from the World Health Organization Consultation on HSV Vaccine Impact Modelling.

Science.gov (United States)

Gottlieb, Sami L; Giersing, Birgitte; Boily, Marie-Claude; Chesson, Harrell; Looker, Katharine J; Schiffer, Joshua; Spicknall, Ian; Hutubessy, Raymond; Broutet, Nathalie

2017-06-21

Development of a vaccine against herpes simplex virus (HSV) is an important goal for global sexual and reproductive health. In order to more precisely define the health and economic burden of HSV infection and the theoretical impact and cost-effectiveness of an HSV vaccine, in 2015 the World Health Organization convened an expert consultation meeting on HSV vaccine impact modelling. The experts reviewed existing model-based estimates and dynamic models of HSV infection to outline critical future modelling needs to inform development of a comprehensive business case and preferred product characteristics for an HSV vaccine. This article summarizes key findings and discussions from the meeting on modelling needs related to HSV burden, costs, and vaccine impact, essential data needs to carry out those models, and important model components and parameters. Copyright © 2017. Published by Elsevier Ltd.

Humoral Immunity to Primary Smallpox Vaccination: Impact of Childhood versus Adult Immunization on Vaccinia Vector Vaccine Development in Military Populations.

Directory of Open Access Journals (Sweden)

Bonnie M Slike

Full Text Available Modified Vaccinia virus has been shown to be a safe and immunogenic vector platform for delivery of HIV vaccines. Use of this vector is of particular importance to the military, with the implementation of a large scale smallpox vaccination campaign in 2002 in active duty and key civilian personnel in response to potential bioterrorist activities. Humoral immunity to smallpox vaccination was previously shown to be long lasting (up to 75 years and protective. However, using vaccinia-vectored vaccine delivery for other diseases on a background of anti-vector antibodies (i.e. pre-existing immunity may limit their use as a vaccine platform, especially in the military. In this pilot study, we examined the durability of vaccinia antibody responses in adult primary vaccinees in a healthy military population using a standard ELISA assay and a novel dendritic cell neutralization assay. We found binding and neutralizing antibody (NAb responses to vaccinia waned after 5-10 years in a group of 475 active duty military, born after 1972, who were vaccinated as adults with Dryvax®. These responses decreased from a geometric mean titer (GMT of 250 to baseline (30 years with a GMT of 210 (range 112-3234. This data suggests limited durability of antibody responses in adult vaccinees compared to those vaccinated in childhood and further that adult vaccinia recipients may benefit similarly from receipt of a vaccinia based vaccine as those who are vaccinia naïve. Our findings may have implications for the smallpox vaccination schedule and support the ongoing development of this promising viral vector in a military vaccination program.

The pharmaceuticalization of sexual risk: vaccine development and the new politics of cancer prevention.

Science.gov (United States)

Mamo, Laura; Epstein, Steven

2014-01-01

Vaccine development is a core component of pharmaceutical industry activity and a key site for studying pharmaceuticalization processes. In recent decades, two so-called cancer vaccines have entered the U.S. medical marketplace: a vaccine targeting hepatitis B virus (HBV) to prevent liver cancers and a vaccine targeting human papillomavirus (HPV) to prevent cervical and other cancers. These viruses are two of six sexually transmissible infectious agents (STIs) that are causally linked to the development of cancers; collectively they reference an expanding approach to apprehending cancer that focuses attention simultaneously "inward" toward biomolecular processes and "outward" toward risk behaviors, sexual practices, and lifestyles. This paper juxtaposes the cases of HBV and HPV and their vaccine trajectories to analyze how vaccines, like pharmaceuticals more generally, are emblematic of contemporary pharmaceuticalization processes. We argue that individualized risk, in this case sexual risk, is produced and treated by scientific claims of links between STIs and cancers and through pharmaceutical company and biomedical practices. Simultaneous processes of sexualization and pharmaceuticalization mark these cases. Our comparison demonstrates that these processes are not uniform, and that the production of risks, subjects, and bodies depends not only on the specificities of vaccine development but also on the broader political and cultural frames within which sexuality is understood. Copyright © 2013 Elsevier Ltd. All rights reserved.

Development of novel double-decker microneedle patches for transcutaneous vaccine delivery.

Science.gov (United States)

Ono, Akihiko; Azukizawa, Hiroaki; Ito, Sayami; Nakamura, Yuki; Asada, Hideo; Quan, Ying-Shu; Kamiyama, Fumio; Katayama, Ichiro; Hirobe, Sachiko; Okada, Naoki

2017-10-30

Microneedle (MN) patches have great potential as transcutaneous vaccine delivery devices because MNs can effectively deliver vaccine antigen into the skin through the micropores formed in the stratum corneum by low-invasive and painless skin puncturing. This study aims to develop novel double-decker MN patches which have not only high safety and efficacy but also broad applicability to various vaccine antigens. We developed two types of MN patches (PGA-MN and Nylon-MN) that are made from polyglycolic acid and Nylon-6. In pre-clinical studies, both MN patches could demonstrably deliver antigens into resected human dermal tissue, prolong antigen deposition and increase antigen-specific IgG levels after vaccination compared with conventional injections. We demonstrated both MN patches could be safely applied to human skin because no broken MNs or significant skin irritation were observed after applications in the clinical research. PGA-MN was suggested to be superior to Nylon-MN regarding human skin puncturability based on measurements of transepidermal water loss and needle failure force. A high content of tetravalent influenza hemagglutinin antigens loaded on PGA-MN could stably maintain HA titers at 35°C for 1year. Overall, double-decker MN patches can reliably and safely puncture human skin and are promising as effective transcutaneous vaccine delivery devices. Copyright © 2017 Elsevier B.V. All rights reserved.

Performance of rotavirus vaccines in developed and developing countries

OpenAIRE

Jiang, Victoria; Jiang, Baoming; Tate, Jacqueline; Parashar, Umesh D; Patel, Manish M

2010-01-01

The World Health Organization estimates that rotavirus diarrhea results in approximately half a million deaths and approximately 2.4 million hospitalizations in developing countries each year. Two live oral rotavirus vaccines, RotaTeq® (RV 5; Merck) and Rotarix® (RV 1; GlaxoSmithKline) with good efficacy against severe rotavirus disease and a reassuring safety profile could substantially impact the burden of rotavirus disease. In April 2009, WHO provided a recommendation for global introducti...

The Potential of Vaccines for the Control of AIDS

Directory of Open Access Journals (Sweden)

Margaret I Johnston

1994-01-01

of attenuated and whole-killed products have led to the pursuit of alternativc designs. including recombinant proteins, vectors and particles, synthetic peptides and naked DNA. Seven recombinant envelope. two recombinant vector and four other candidate vaccines that have entered into phase 1 trials in noninfected individuals have proven safe to date, and have differed In their ability lo induce functional antibody and Cytotoxic T lymphocytes. Two recombinant envelope products have recently progressed to phase 2 testing, Five envelope-based and six other products have entered trial in HIV-infected and individuals and have appeared to be safe, Evidence of new antibody, increased T cell proliferation and lncreased cytotoxic T lymphocyte activity have been reported. Additional placebo controlled trials will be required to evaluate the impact of therapeutic vaccination on CD4 cell count. viral burdrn and clinical end-points. The status of HIV/AIDS vaccine development is reviewed. with emphasis on the challenging task of finding an effieacious, safe, prophylactic vaccine.

Trivalent MDCK cell culture-derived influenza vaccine Optaflu (Novartis Vaccines).

Science.gov (United States)

Doroshenko, Alexander; Halperin, Scott A

2009-06-01

Annual influenza epidemics continue to have a considerable impact in both developed and developing countries. Vaccination remains the principal measure to prevent seasonal influenza and reduce associated morbidity and mortality. The WHO recommends using established mammalian cell culture lines as an alternative to egg-based substrates in the manufacture of influenza vaccine. In June 2007, the EMEA approved Optaflu, a Madin Darby canine kidney cell culture-derived influenza vaccine manufactured by Novartis Vaccines. This review examines the advantages and disadvantages of cell culture-based technology for influenza vaccine production, compares immunogenicity and safety data for Optaflu with that of currently marketed conventional egg-based influenza vaccines, and considers the prospects for wider use of cell culture-based influenza vaccines.

[The small pox vaccine: its first century in Brazil (from the Jennerian to the animal vaccine)].

Science.gov (United States)

Fernandes, T

1999-01-01

Covering a period of roughly hundred years, the article looks at some of the more meaningful events during the period in which the small pox vaccine was institutionalized in Brazil. Discoveries and discussions then taking place in other countries are also examined, particularly as they influenced Brazil. The process is followed from introduction of the human vaccine to the arrival of the animal vaccine and creation of the Municipal Vaccine Institute--a private initative by physician Pedro Affonso Franco, also known as the barao de Pedro Affonso. Adoption of the animal vaccine not only represented progress in controlling the disease but also spurred discussions that saw medical and political groups in Brazil taking sides with either Oswaldo Cruz or the barao de Pedro Affonso. The debate continued within the academic and political arenas until the Vaccine Institute was made part of the Manguinhos laboratories.

BCG vaccination reduces risk of tuberculosis infection in vaccinated badgers and unvaccinated badger cubs.

Directory of Open Access Journals (Sweden)

Stephen P Carter

Full Text Available Wildlife is a global source of endemic and emerging infectious diseases. The control of tuberculosis (TB in cattle in Britain and Ireland is hindered by persistent infection in wild badgers (Meles meles. Vaccination with Bacillus Calmette-Guérin (BCG has been shown to reduce the severity and progression of experimentally induced TB in captive badgers. Analysis of data from a four-year clinical field study, conducted at the social group level, suggested a similar, direct protective effect of BCG in a wild badger population. Here we present new evidence from the same study identifying both a direct beneficial effect of vaccination in individual badgers and an indirect protective effect in unvaccinated cubs. We show that intramuscular injection of BCG reduced by 76% (Odds ratio = 0.24, 95% confidence interval (CI 0.11-0.52 the risk of free-living vaccinated individuals testing positive to a diagnostic test combination to detect progressive infection. A more sensitive panel of tests for the detection of infection per se identified a reduction of 54% (Odds ratio = 0.46, 95% CI 0.26-0.88 in the risk of a positive result following vaccination. In addition, we show the risk of unvaccinated badger cubs, but not adults, testing positive to an even more sensitive panel of diagnostic tests decreased significantly as the proportion of vaccinated individuals in their social group increased (Odds ratio = 0.08, 95% CI 0.01-0.76; P = 0.03. When more than a third of their social group had been vaccinated, the risk to unvaccinated cubs was reduced by 79% (Odds ratio = 0.21, 95% CI 0.05-0.81; P = 0.02.

The multi-epitope polypeptide approach in HIV-1 vaccine development.

Science.gov (United States)

Cano, C A

1999-11-01

The application of a preventive HIV vaccine is the only hope for most developing countries to halt the AIDS pandemic. A project aimed to develop a preventive AIDS vaccine is being carried out since 1992 by three Cuban research institutions: Centro de Ingeniería Genética y Biotecnologia de La Habana, Instituto de Medicina Tropical 'Pedro Kouri' and Laboratorio de Investigaciones de SIDA de La Habana. The project includes two main strategies: (a) generation of recombinant multi-epitope polypeptides (MEPs) bearing several copies of the V3 loop from different HIV-1 isolates; and (b) development of immunogens capable of inducing a cytotoxic T cell response (CTL) specific for human immunodeficiency virus type 1 (HIV-1) antigens. This article summarizes the work in the first of these strategies. Based on the sequence of the V3 loop of HIV-1 we constructed a series of MEPs and evaluated their immunogenicity in mice, rabbits and macaques. The MEP TAB9, containing six V3 epitopes from isolates LR10, JY1, RF, MN, BRVA and IIIB, was selected together with the oil adjuvant Montanide ISA720 (SEPPIC, France) to perform a Phase I clinical trial in HIV seronegative Cuban volunteers. The trial was double blinded, randomized, and fulfilled all ethical and regulatory requirements. All TAB9 vaccinated volunteers developed a strong immune response and neutralizing antibodies were observed in the 50% of the subjects. However the second and third inoculations of the vaccine were not well tolerated because transient severe local reactions appeared in some individuals. A new formulation of TAB9 is currently in pre-clinical studies and is expected to enter clinical trials in 1999.

Plague Vaccines: Status and Future.

Science.gov (United States)

Sun, Wei

2016-01-01

Three major plague pandemics caused by the gram-negative bacterium Yersinia pestis have killed nearly 200 million people in human history. Due to its extreme virulence and the ease of its transmission, Y. pestis has been used purposefully for biowarfare in the past. Currently, plague epidemics are still breaking out sporadically in most of parts of the world, including the United States. Approximately 2000 cases of plague are reported each year to the World Health Organization. However, the potential use of the bacteria in modern times as an agent of bioterrorism and the emergence of a Y. pestis strain resistant to eight antibiotics bring out severe public health concerns. Therefore, prophylactic vaccination against this disease holds the brightest prospect for its long-term prevention. Here, we summarize the progress of the current vaccine development for counteracting plague.

Architectural Insight into Inovirus-Associated Vectors (IAVs and Development of IAV-Based Vaccines Inducing Humoral and Cellular Responses: Implications in HIV-1 Vaccines

Directory of Open Access Journals (Sweden)

Kyriakos A. Hassapis

2014-12-01

Full Text Available Inovirus-associated vectors (IAVs are engineered, non-lytic, filamentous bacteriophages that are assembled primarily from thousands of copies of the major coat protein gp8 and just five copies of each of the four minor coat proteins gp3, gp6, gp7 and gp9. Inovirus display studies have shown that the architecture of inoviruses makes all coat proteins of the inoviral particle accessible to the outside. This particular feature of IAVs allows foreign antigenic peptides to be displayed on the outer surface of the virion fused to its coat proteins and for more than two decades has been exploited in many applications including antibody or peptide display libraries, drug design, and vaccine development against infectious and non-infectious diseases. As vaccine carriers, IAVs have been shown to elicit both a cellular and humoral response against various pathogens through the display of antibody epitopes on their coat proteins. Despite their high immunogenicity, the goal of developing an effective vaccine against HIV-1 has not yet materialized. One possible limitation of previous efforts was the use of broadly neutralizing antibodies, which exhibited autoreactivity properties. In the past five years, however, new, more potent broadly neutralizing antibodies that do not exhibit autoreactivity properties have been isolated from HIV-1 infected individuals, suggesting that vaccination strategies aimed at producing such broadly neutralizing antibodies may confer protection against infection. The utilization of these new, broadly neutralizing antibodies in combination with the architectural traits of IAVs have driven the current developments in the design of an inovirus-based vaccine against HIV-1. This article reviews the applications of IAVs in vaccine development, with particular emphasis on the design of inoviral-based vaccines against HIV-1.

Development of a rotavirus vaccine: clinical safety, immunogenicity, and efficacy of the pentavalent rotavirus vaccine, RotaTeq.

Science.gov (United States)

Ciarlet, Max; Schödel, Florian

2009-12-30

Initial approaches for rotavirus vaccines were based on the classical "Jennerian" approach and utilized simian and bovine rotavirus strains, which provided cross-protection against human rotavirus strains but did not cause illness in infants and young children because of their species-specific tropism. The demonstrated efficacy of these vaccines was not consistent across studies. Thus, human-animal reassortants containing an animal rotavirus backbone with human rotavirus surface G and/or P proteins were developed, which demonstrated more consistent efficacy than that observed with the non-reassortant rotavirus strains. The pentavalent rotavirus vaccine, RotaTeq, contains 5 human-bovine reassortant rotaviruses consisting of a bovine (WC3) backbone with human rotavirus surface proteins representative of the most common G (G1, G2, G3, G4) or P (P1A[8]) types worldwide. The present review focuses on the development of the pentavalent rotavirus vaccine RotaTeq. Results of a large-scale Phase III clinical study showed that three doses of RotaTeq were immunogenic, efficacious, and well tolerated with no increased clinical risk of intussusception. RotaTeq was efficacious against rotavirus gastroenteritis of any severity (74%) and severe disease (98-100%), using a validated clinical scoring system. Reductions in rotavirus-associated hospitalizations and emergency department (ED) visits, for up to 2 years post-vaccination, were 95% in Europe, 97% in the United States, and 90% in the Latin American/Caribbean regions. RotaTeq was recently shown to be up to 100% effective in routine use in the US in reducing hospitalizations and ED visits and 96% effective in reducing physician visits. Additional studies in 8 different locations in the US have shown 85-95% reduction in rotavirus-associated hospitalizations and/or ED visits in the first 2-2.5 years of routine use.

How can plant genetic engineering contribute to cost-effective fish vaccine development for promoting sustainable aquaculture?

Science.gov (United States)

Clarke, Jihong Liu; Waheed, Mohammad Tahir; Lössl, Andreas G; Martinussen, Inger; Daniell, Henry

2013-09-01

Aquaculture, the fastest growing food-producing sector, now accounts for nearly 50 % of the world's food fish (FAO in The state of world fisheries and aquaculture. FAO, Rome, 2010). The global aquaculture production of food fish reached 62.7 million tonnes in 2011 and is continuously increasing with an estimated production of food fish of 66.5 million tonnes in 2012 (a 9.4 % increase in 1 year, FAO, www.fao.org/fishery/topic/16140 ). Aquaculture is not only important for sustainable protein-based food fish production but also for the aquaculture industry and economy worldwide. Disease prevention is the key issue to maintain a sustainable development of aquaculture. Widespread use of antibiotics in aquaculture has led to the development of antibiotic-resistant bacteria and the accumulation of antibiotics in the environment, resulting in water and soil pollution. Thus, vaccination is the most effective and environmentally-friendly approach to combat diseases in aquaculture to manage fish health. Furthermore, when compared to >760 vaccines against human diseases, there are only about 30 fish vaccines commercially available, suggesting the urgent need for development and cost-effective production of fish vaccines for managing fish health, especially in the fast growing fish farming in Asia where profit is minimal and therefore given high priority. Plant genetic engineering has made significant contributions to production of biotech crops for food, feed, valuable recombinant proteins etc. in the past three decades. The use of plants for vaccine production offers several advantages such as low cost, safety and easy scaling up. To date a large number of plant-derived vaccines, antibodies and therapeutic proteins have been produced for human health, of which a few have been made commercially available. However, the development of animal vaccines in plants, especially fish vaccines by genetic engineering, has not yet been addressed. Therefore, there is a need to exploit

Immunology and evolvement of the adenovirus prime, MVA boost Ebola virus vaccine.

Science.gov (United States)

Zhou, Yan; Sullivan, Nancy J

2015-08-01

The 2014 Ebola virus outbreak caused an order of magnitude more deaths in a single outbreak than all previous known outbreaks combined, affecting both local and international public health, and threatening the security and economic stability of the countries in West Africa directly confronting the outbreak. The severity of the epidemic lead to a global response to assist with patient care, outbreak control, and deployment of vaccines. The latter was possible due to the long history of basic and clinical research aimed at identifying a safe and effective vaccine to protect against Ebola virus infection. This review highlights the immunology, development, and progress of vaccines based on replication-defective adenovirus vectors, culminating in the successful launch of the first Phase III trial of an Ebola virus vaccine. Published by Elsevier Ltd.

User-Centered Design for Developing Interventions to Improve Clinician Recommendation of Human Papillomavirus Vaccination.

Science.gov (United States)

Henninger, Michelle L; Mcmullen, Carmit K; Firemark, Alison J; Naleway, Allison L; Henrikson, Nora B; Turcotte, Joseph A

2017-01-01

Human papillomavirus (HPV) is the most common sexually transmitted infection in the US and is associated with multiple types of cancer. Although effective HPV vaccines have been available since 2006, coverage rates in the US remain much lower than with other adolescent vaccinations. Prior research has shown that a strong recommendation from a clinician is a critical determinant in HPV vaccine uptake and coverage. However, few published studies to date have specifically addressed the issue of helping clinicians communicate more effectively with their patients about the HPV vaccine. To develop one or more novel interventions for helping clinicians make strong and effective recommendations for HPV vaccination. Using principles of user-centered design, we conducted qualitative interviews, interviews with persons from analogous industries, and a data synthesis workshop with multiple stakeholders. Five potential intervention strategies targeted at health care clinicians, youth, and their parents were developed. The two most popular choices to pursue were a values-based communication strategy and a puberty education workbook. User-centered design is a useful strategy for developing potential interventions to improve the rate and success of clinicians recommending the HPV vaccine. Further research is needed to test the effectiveness and acceptability of these interventions in clinical settings.

The yellow fever 17D vaccine virus as a vector for the expression of foreign proteins: development of new live flavivirus vaccines

Directory of Open Access Journals (Sweden)

Myrna C Bonaldo

2000-01-01

Full Text Available The Flaviviridae is a family of about 70 mostly arthropod-borne viruses many of which are major public health problems with members being present in most continents. Among the most important are yellow fever (YF, dengue with its four serotypes and Japanese encephalitis virus. A live attenuated virus is used as a cost effective, safe and efficacious vaccine against YF but no other live flavivirus vaccines have been licensed. The rise of recombinant DNA technology and its application to study flavivirus genome structure and expression has opened new possibilities for flavivirus vaccine development. One new approach is the use of cDNAs encopassing the whole viral genome to generate infectious RNA after in vitro transcription. This methodology allows the genetic mapping of specific viral functions and the design of viral mutants with considerable potential as new live attenuated viruses. The use of infectious cDNA as a carrier for heterologous antigens is gaining importance as chimeric viruses are shown to be viable, immunogenic and less virulent as compared to the parental viruses. The use of DNA to overcome mutation rates intrinsic of RNA virus populations in conjunction with vaccine production in cell culture should improve the reliability and lower the cost for production of live attenuated vaccines. The YF virus despite a long period ignored by researchers probably due to the effectiveness of the vaccine has made a come back, both in nature as human populations grow and reach endemic areas as well as in the laboratory being a suitable model to understand the biology of flaviviruses in general and providing new alternatives for vaccine development through the use of the 17D vaccine strain.